yep,looking at what you are doing when this presents itself would help alot in finding the cause. create a little "journal' of this ongoing situation, believe me, it will help tons when you will more than likely have to have this evaluated to look for the underlying cause.
the thing is,this could be stemming anywhere from the wrists on up thru that shoulder and into where its base is, at the c spine level. all of the three nerves that innervate all of our fingers and hand start up at the c 5-6 thru c 8(nerve) area in the c spine. then there is also at the very cord level too,but that would be a bit less common with what you have been describing. if this persists or gets worse,it should at least be evaluated by your doc who could send you for an MRI of that c spine. there are other nerve tests that can be run too that would show any actual nerve impingement. something like carpal tunnel syndrome can do this too. that involves the median nerve that runs thru the wrist and into the fingers.
just keep note of all symptoms and what you were doing when they started and if there are any particular fingers that are only involved as well. that would help track it back up to the corresponding c spine nerve that just innervates it. but if i were you, i would see your primary soon just to get the ball rolling withsome simple testing to see where this is actually being affected. there are two things can affect our fingers with numbness or tingling in most cases, either the nerves themselves or a vascular flow issue. please keep us posted as to what you find out. FB