Your first few lifts/workouts are going to leave you messed up for a few days. I would only start to worry if it hurts more than five days out. After your second or third session though you should recover much quicker, within a day or so. It's because you're reengaging muscles that haven't been used in that way for anywhere near that intensity, as well as specifically targeting muscles rather than using multiple muscle groups. How many times do you do 3x10 squats with 45 pounds (or whatever your routine is) outside of lifting? Probably never, and that's why it hurts to sit down.

Don't put off lifting again even if it hurts. It won't get any worse than your first day. You can mitigate it a little by warming up, cooling down (I usually just walk home after), icing or taking a short cold bath asap after your lift, applying heat later, regularly stretching the muscles you exercised, eating enough food, and drinking enough water. Like I said though, within two weeks of doing your routine you'll be recovering within 48 hours and outside of the warmup, occasional stretching, and getting enough food and water, you shouldn't need to do the other stuff.