Re: Muscle / Nerve Twitching
My personal research into this problem hasn't come up with anything conclusive. It could be anything from a vitamin/mineral deficiency (magnesium and potassium in particular), to side-effects from other medicines, to anxiety/stress - that's before you consider anything more serious.
Seeing a neurologist is the best course of action, and is probably the only way you'll really find out what the cause is. I wouldn't worry about it being anything major though - as I've said, stress/anxiety can make these 'symptoms' worse, or even be the sole cause of the problem.