Running

I just had a run before, and towards the end I can feel that knee stiffness typical of IT band (I'm going to foam roll etc and sort that out), but..

I was sitting down and noticed my kneecap is slightly irritable. I just started moving the skin around on my kneecap to find out where the pain is coming from and had a sharp twinge of pain. I wasn't being forceful in any way.

On my left knee it's on the right side, at the bottom that it's painful.

I think tendon pain, right?