Low Back Pain/Tightness

About 2 months ago, I was squatting but it got too tight and painful and I called it quits. I have not squatted since. I have been doing powerlifting now for two years and have not had this problem. For awhile, I was having a dull pain along with a sharp pain in my left hip/groin area. However, it is my back that is causing problems.

I have been going to physical therapy for over a month now and my low back does not feel any better. I have done strengthening of the hip, core, glutes, and back. I have also done stretches but that seems to make my back worse. It feels good when I do them, but gets worse afterwards. I really don’t know what to do. Nothing seems to work. Any ideas?