Could have been just the position your arm, hand and fingers were in. Could have triggered a nerve.

I have done that in my legs and feet, there are so many strange things but many of us have them, maybe not strange at all.

I have twitching fingers in my hands when holding a fork while eating (occasionally) and while holding newspapers and books. I have switched to reading the papers on a computer and I read books on an NOOK.

Yes,Ive experienced this before in a few of my fingers. All of a sudden I've been woken up by it because it's like a quick jolty twitch and it really hurts that second. Hasn't happened for a while now though.