Good afternoon a few months ago, I began to feel pain in the back of my leg when exercising. My orthopedist told me that it was just a mild hamstring tear and recommended rest and physical therapy. After four months of rest and physical therapy, the pain persists. Also, I notice that it increases when I walk too much. I had an mri and no injury was found. Therefore, I don't know what is happening, and I don't know what to do to get rid of pain. What injury may be causing the pain? What can I do to relieve it? Thank you.