I can relate to the twitching. It is very annoying at the least and scary at the worst. It has been going on for me for the past year. The more I think about them the more they occur. Some days they don't occur at all and I will say to myself I didn't have a twitch today and sure enough they start. Of course, one starts to be afraid of the all the disease such as MS, ALS and all the rest but that doesn't appear to be the case. They are primarily when I am resting and no lost of strength and coordination and all that good stuff. My doctor just seems to blow it off as an anxiety symptom and does not pursue any other testing. I have been going to the same doctor for years so I have to trust her to a certain extent.
Taking vitamins does seem to help, avoiding caffiene and being active does help. But dealing with stress is really the key. The past two years have been difficult but I keep pushing forward. Anxiety has so many symptoms and I have seem to have had them all. I am not sure what your religious beliefs are but my therapist mentioned giving in to the anxiety symptoms and when I am feeling bad I just say to my self. I surrender Lord, do with me as you please. I don't try to fight it anymore. if my worse fears are true and I am dying of some horrible disease it sure is taking a long time. :) But seriously, see your doctor and know that there are many who suffer the same daily aggravation we do and are just fine.