So I've been doing the stronglifts program for about a year or so. I got to the goal of 1.5x body weight on a 1 rep max and actually exceeded it by being able to do a full 5x5 set of 235lbs @ 155lb body weight Now at some point last thursday I was doing my squat and deadlift. When I finished, I felt my lower back kinda tight. I took a week off and when I went to squat yesterday again at a much lighter weight. I hurt my back again, this time worse, I could hardly even drive in my car. Couldn't even bend down to touch my toes and I can usually lay my hands flat on the ground. I went to the chiropractor, and he's helped me alot (I feel much better than this morning) and he just said I may have done something wrong and re-injuring it will be much easier. What may I have done wrong? I've never had lower back problems, I'm 26. I always strive to maintain proper form. I'm really disappointed by this as squat has become one of my favorite exercises in the gym and I thought I was really doing it right. How long should I stay away from back squat and deadlift? How should I approach it on returning to it? And what other exercises should I do to replace or prevent future injury?