Hello~I am sorry you are having these issues.
Are your arms and hands weak? Do you have strength in them to lift or hold things like you could before this happened? Have you seen a doctor for this? I don't like to be an alarmist, but it wouldn't hurt to see your GP and tell him about it, he might want to do some tests to rule out Parkinson's, but with it, you usually are weak in the areas that are twitching. For peace of mind, I would ask.
Also, the twitching could be due to low calcium and magnesium, try taking a high-potency mult-mineral supplement along with an electrolyte supplement. Any good health store will carry these.
Last, but certainly not least, try see a chiropractor, you could have some pinched nerves in your neck and upper back, if that is the case, this, too, can cause muscle twitching.
I hope it stops soon, I know how annoying even a small twitch of the eye can be, I am sure you are most uncomfortable.