I'm going to be a senior in high school this fall. I had a very successful xc season last year, with a decent but slightly disappointing track season. I'm one week into summer training and decided to do a local road race 5K with some friends to see where I'm at for the beginning of the summer. On our little warm up trot, I suddenly started feeling a sharp pain right below my kneecap. I wasn't too worried and ran anyway, since we weren't taking the race too seriously. It was pretty painful for the first mile, and I was regretting my decision to run through it, but halfway into the race the pain went away. I was able to run just barely sub-17, which I am quite satisfied with considering my PR is 16:13. I took Sunday off and this morning went out for my long run and had to stop early because the pain was back and got worse as the run progressed. It does not hurt at all when I walk around, only when I run. Anyone know what it could be? I plan on not running for at least 4 days and then seeing how it feels.