I Injured My Back Doing Squats About 5 Weeks Ago.

I injured my back doing squats about 5 weeks ago. However, as long as I am not lifting heavy weights, I can perform intense exercise on a daily basis with no pain, only a little stiffness from time to time. However, once or twice a day when I am bending over to put shoes on etc., I experience a sudden shock of severe pain in my lower back along my spine. It goes away very quickly, and I can go on with my day as if nothing happened. I haven't lifted any heavy weights since I first experienced this 5 weeks ago. Should I be worried that it is still occuring?