Joint Pain (strange)

I seem to have a strange pain in my joints (two so far). First was my left knee on the outside. Then a few months after now my right ankle on the inside has the same symptoms.

The pain is sporadic but sharp and does not come on from any thing particular and doesn't seem to bother me in most of my day to day activities. Even running a fair distance gives me no trouble at all.

When I do stretch the joint in some way, as in kneeling down on my knee (My knee is not so bad anymore BTW)or when I might stretch/point out my foot, there is a very sharp pain.

The pain is very similar to having a stabbing splinter or the reopening of a scab or cut. At one point with my knee I even dropped my pants certain that my skin had ripped open. It is not a deep pain and feels as if it is on the surface but both times it was on the side of the joint.

Any ideas?

Rice