First off, have you seen a doctor about this? Currently i'm not at all a fan of doctors right now because of what's happen to me, but they are the only "professional" resource. Still, I know this may not be a big enough problem to visit the hospital but at least it's a start.

Forking cash out for a doctor to tell you his opinion (good or bad), is up to you, though from what you've mentioned it doesn't sound like a big problem.

I say if it continues, and especially if the numbing starts lasting longer, i'd see professional help.

Good luck