Are there any neurotransmitter imbalances that would cause muscle twitching all over body?

What an odd question: The role of neurotransmitters in myoclonus is still under study. What you're describing can be caused by problems elsewhere in the body, and in fact very often is. The brain is just an unfortunate bystander. The underlying cause is what needs to be found. See your doctor and let him/her figure it out. And I'm afraid if you bring up neurotransmitters, you'll probably just get a blank stare.