I have never had or been treated for, knee problems. I went to kneel down on my knees to pick something up and I thought I must have kneeled on a small toy because of the instant stinging/burning pain of my left knee cap. I can push on that area with my fingers and produce the same pain. What might be going on?
HIT his is likely bursitis, and it should resolve in a few days with heat, rest and ibuprofen.  If it persists, you need an MRI of the knee to determine exactly what the problem is