Being overwhelmed like you're describing, to me, is like a ratchet – it increases bit by bit, sometimes gradually and sometimes in big increments, but by the time you're verging on a meltdown or a shutdown it's ratcheted up to a critical point.

While self-care after you hit that point is obviously very important, I don't think it's fair on yourself to assume that 1 hour in an overwhelming situation that is so intense that it's pushing you to the point of flipping out can be fixed by spending 1 hour chilling out after the fact.

More than that, when your nervous system is at that point it's very difficult to engage in the activities that are calming and soothing because you're in a state that is too heightened, and I think this is where acute burnout happens. If I'm doing a bad job of explaining what my take is here, imagine a person who is having a panic attack - by their very circumstances they aren't going to be able to have a very deep, rewarding meditation session. If they are able to, engaging in meditative or mindfulness sort of activities can absolutely reap benefits to help loosen the grip of the panic attack, there's no doubt about that, but in the midst of a panic attack calming yourself is only ever likely to reduce the severity/intensity of that heightened state but it's almost certainly not going to be restful or refreshing in the way that it would be if you approached the same exercise from a place where you are feeling regulated and centred.

This is a parallel to being in a state of sensory overload or other experiences of being overwhelmed.

You might take hours or days, perhaps even longer, to gear down from being overwhelmed especially if you've been at that critical point for a prolonged period of time or it's happened repeatedly in fairly short succession.

One of the ways to manage this is to try to find opportunities to take breaks, even if they are brief. Headphones on or earplugs in, sitting in a quiet and calm space, allowing yourself the opportunity to settle somewhat - that sort of thing. If you're out at a function or something like that, it might be that you excuse yourself and spend a few minutes in the bathroom just centering yourself or stepping outside to somewhere quiet for a breather.

The other thing is addressing your sensory diet and auditing your sensory experience. This sounds complicated but it's really not. I need to make a post about this but the shorthand version of it is this: the opposite of negative sensory stimuli isn't the absence of the stimuli but rather the presence of positive sensory stimuli. You want to try and stack up as much positive sensory stimuli as possible (within reason) while limiting and avoiding the negative stimuli where you can. If you can crowd out the bad with the good, your nervous system won't be as overwhelmed and you'll bounce back quicker.

The sensory domains are tactile (touch/texture), visual (sight), olfactory (smell), gustatory (taste), auditory (sound), vestibular (your body's balance and orientation in space), and proprioceptive (your sense of your body itself).

If you feel inclined, make pages (virtual or physical) with two columns, one for good and one for bad, with a heading for each sensory domain. Try to fill out each column as best you can. You'll likely do better with the bad than the good especially to begin with. Remember to record when you encounter a particularly strong sensory experience in your day-to-day life, then add it to the appropriate page and column. You might find a particular smell like an essential oil, a perfume, or a type of incense especially positive or negative when you experience it. Record it. If you find the smell of peppermint to be positive then you will almost certainly find the taste of it good, so test it and record that too. Try to chase those leads where they take you. For example if you like the smell of sandalwood (or if you hate it) then the same probably applies for cedarwood. If you like sour candy then you will probably like lemon, lime, and tamarind (also amchur because I'm on a crusade to raise awareness of amchur on this site so I am trying to find any opportunity to mention it.) If you don't like the feeling of microfibre then you probably won't like the feeling of velour or velvet. If you like the feeling of rocking then you'll probably like the feeling of swinging. If you like the feeling of water flowing over your skin then you'll probably like the feeling of air flowing over your skin. And so on.

Once you've mapped out a good deal of the things that you like then the next step is to try and find ways to incorporate these sensory experiences into your everyday life. Maybe that means having a lava lamp or ceiling projector on a timer in your bedroom so that when you're winding down in the evening, you get compulsory positive sensory stimuli time. Or maybe it's about putting some diffusers around your house with the right fragrance or having an electric essential oil burner on a timer in your space etc.

This will help a lot in the long term but it's probably not going to be an immediate fix for you.

On the bad side, once you've fleshed out your lists the next step is to strategise for mitigating and avoiding these things. Maybe it means changing your wardrobe, getting ear defenders or loop-style devices (there are cheap knockoffs on aliexpress and similar sites!) or active noise cancelling headphones, catching public transport to avoid peak hour, preparing in advance so you can avoid tobacco smoke because you know you hate it so when someone nearby is about to light up you move away from them before the smell becomes overwhelming for you etc. By taking this approach, you will be more proactive at managing the things that overwhelm you and push you into a state or being overwhelmed and shutting down/melting down/burning out. If we imagine a scale from 0-10, with 10 being excruciating and 0 being the absence of the bad stimuli, maybe it takes for that experience to hit a 5 or a 6 before you typically take steps to deal with it. Maybe you don't even get that chance and it immediately hits a 7 or 8 because you suddenly find yourself in a cloud of second-hand cigarette smoke or really bad traffic noise. That's going to really strain your nervous system much more than it would if you have something to manage that traffic noise and you're using it before you even get exposed to it, so that way you only experience it at a 2 or a 3. Same goes for getting out of the way when someone pulls out a cigarette - instead of being caught unawares and finding yourself breathing in that smoke, you will be able to move away before they light up and you'll only experience the bad smell at 3 or a 4 instead of an 8 or 9.

(To overcomplicate this somewhat, I don't think that sensory experiences scale linearly for us and it's more exponential, sort of like how decibels or pH works, where a low-level bad stimuli at a 1 or 2 is going to be tolerable for a very long time, and perhaps all day or longer, whereas a 7 or 8 is going to be tolerable for only a brief amount of time before it completely overwhelms you. If you can preempt the bad sensory stimuli or you are more attuned to your sensory experience then it won't take until it's at a 6 before you become aware of it and start trying to deal with it. In this way you're going to incur less damage to your sensory health bar, if that makes sense.)

Over time you want to create habits or maybe even instinctual responses to address negative sensory stimuli and to experience more positive sensory stimuli, and in this way you'll have a healthier sensory diet so you will find that you cope better overall.