Back Pain

I have been reading a lot of articles on this site and they are great. My back used to be severe but now i got it to be manageable. But, i tried yoga the other day and absolutely killed my back (stupid of me to do all those flexion exercises), anytime i bend forward, i have pain in my lower back on the right side. (Top part of the glutes?)

Any ways, i need some help identifying this pain and would like to get rid of it. I have not done any deadlifts or squats in a long time due to this injury and would like to get back into it.