What Causes Pain On Knee Surface After Recovery From Injury?

I was playing basketball a few months ago and fell. My knee was the first thing to hit and all that was injured. The initial pain and discomfort is gone but the skin/knee cap is very sore to the touch at one particular spot. I originally thought it was my knee cap that was still bruised but as I continued to investigate, it seems as though it's the actual skin that causes the sharp pain when touched. Any ideas?