I had a lower back injury while lifting something heavy 1.4 months back. After that i had a dull back pain. I dont have any sharp or radiating pain. I can do all exercises normally. Initially pain was left lower bsck but now it has shifted ro right mostly. Sometimes its constant. I started physio 2 days back. Did some stretches. Tightness jn thig is gone. But i am feeling tightness jn calf and knee area in right leg. I also feel a burning sensation sometime in bottom of right foot. What could be the reason ?