idk wtf I did but I woke up 2 days ago with this pain in my shoulder right inside where the shoulder itself meets my chest and man it hurts. It's so bad in the morning I can't lift my arm over my head. But as the day goes on (and taking some nsaids) it lessens a bit.
What did I do to myself?
I did something like that a year or so ago. Turned out to be nerve impingement for me.
Frontier medicine note: Musculoskeletal injuries are fairly easy to self-diagnose since there's a shitload of physical therapy resources telling you how to test for (or rule out) specific injuries by moving/stretching/etc. Also pretty easy to look up the requisite treatments, which are often exercises or stretches.