Bilateral Quadricep Tendinosis

I have 2 existing shoulder injuries, (left labrum) (right supraspinatus tendinosis), so In january doctors told me to lay low for a month. At the end of that month i decided too take a walk to the bank, a mile tops there and back. I did a few calf stretches before and went.

Got back no injury, no pain. That night i woke up with the worst a pain on the insides of my knee and stiffness. The stiffness went away but the pain is still here.

Ive been doing stretches that my physical therapists recommended for the quads and that seems to help. I tried strengthening for a week and felt like it was getting better, the week after it started hurting again.

Any tips on the matter would be helpful.. these doctors are full of shit.