L5S1 herniation. Without thinking pain.

Myself  is suffering heavy knee pain from 4 Monthand little back pain . Initially, Doctor adviced to take left Knee MRI and their impression is "POST TRAUMATIC CHONDROMALACIA PATEELAE -GRADE 2" and the observation is "partial thickness erosion /loss of articular cartilage over the medial patellar facet." Doctor said no obnormality in Knee then adviced to take LS  MRI and the impression result are " Reduced L5S1 intervertebral disk space with adjucent end plate degeneration,Posteriocentral disc protrusion at L5s1 level impingement on bilateral zone 1 nerve root (L>R), Annular Blige at L4 L5 level" .Nerve Conductin study shows normal . Based on MRI doctor advised to go for physiotherophy and take some medicine like pain killer,neurobion and iron tablet .Now the pain is reduced in left knee where as  right knee has same heavy pain . Doctor said you have spin issue but the knee pain is not because of that .But no conclusion given by doctor and do your regular duties without thinking pain .