I mildly sprained my ankle (in a bike crash, although I have no idea how, and didn't notice until several days later) a few months ago. When I finally went to the doctor, they said it was fine to ride if it didn't hurt to do so. If it DID hurt, then they said absolutely not. So really, DON'T ride if it hurts to ride.

That was in March and I still have some problems with fluid build up in that ankle on long rides. I wear an Ace ankle support to prevent this. Otherwise I've had enough edema in the ankle to cause bruising - yuck.

Take it easy, and make sure you pay close attention to it once you start riding again.