Yeah, it happens to me sometimes too. Checked it in the mirror, but it doesn't show to other people. And if it did, what the hell?
It's a common thing btw. People get twitches all the time ;-)
i've had eyelid twitches when I'm tired - most bizarre feeling. Happened during a round the table meeting at work once, I was wondering whether anyone noticed but apparently not.
I think its more like something you feel, but don't see. I looked in the mirror once and couldn't see anything. 'Spose because the eye area is full of nerves it feels like its worse than it is.