So yeah, did squats today, same weight I've been doing for 3 months (225). Was on my second set when I leaned forward a little too much on a deep squat, and had to use a lot of lower back to get straight and make it up. Kept working out this morning. About 3 hours later, back started hurting. By the evening I have barely been able to move. I can't tell if it's soreness or injury, because it's right at the small of my back, at the hips. Can barely stand up once I've sat down and it's tough to get comfortable. FUCK. Hope it's just a strain or major soreness, but luckily I happened to have a doctor's appointment for my knee and shoulder on tues anyway.