Low Back Pain

My low back pain flare up again.  I fell off my bike and bumped on my buttocks.  With my weight, I am sure the vertebra on my spine shift.  Also when I twist my back after, I felt the clicks.  Unfortunately, the clicks did not shift my vertebra back in their original position.  So I am having dull ache and I worry may cause my back to "freeze".  I have been suffering from backache since JC time(Pre-U during my time).  Spraining back once and it is chronic pain for life!