Don't know if this is MS, or something else that I had at the time (virus maybe?).
In any event, last year, before my MS diagnosis (fall of 07) I had twitching that began under my right eye. It was non stop from waking to bedtime.
I'd had this in the past, but it never lasted for 2 weeks straight! It was very annoying as well as you can imagine.
Well, that twitching eventually progressed into my cheek (could see the twitching around my nose on the right), then into my mouth/chin on the right (twitching in the chin).
The right side of my mouth looked like it was being pulled upwards. I'd have suspected Bells Palsy if there had been a droop (doctors who saw me at the time thought it may have been like Bells).
I had this for 2-3 months (if memory serves me correctly) and then the twitching just stopped.
All the while, I had the cruddy burning mouth syndrome (which I still have, hoping that will resolve eventually. it's much lessened now in intensity).
I've never since figured out what this facial twitching on 1 side, and the mouth being pulled upwards, could be.
Any clues? Could this have been MS? I've looked at stuff in the past, but you know how the Internet is..

, you can run into a lot of irrelevant junk.