Hey
@Jerbear - half the battle is getting past the worrying. Easy to say - hard to do but seriously for piece of mind see a doctor. They can check your reflexes and if the doc is decent can make an educated guess based on manual manipulation to find which nerve is the issue or what the problem is.
If the doctor doesn't know and send you to a neurologist - don't freak out, he/she is just saying this isn't my specialty so it's best to have someone who can do the proper tests to determine what is going on. They might send you straight to an orthopedic surgeon - they are some of my favorite docs.
Do you have issues buttoning your shirt? Muscle spasms most definitely don't mean a serious disease like ALS, Parkinson's or MS. Those are the zebras they will chase once they eliminate the most likely suspects.
If you want to chat about it - sometimes it helps just to chat or vent, PM me. I'm not a doctor but have been through the same type of issues and went to three neurologists - finally ended up in Montreal at the neurological clinic and then to an infectious disease doc. Long story short - they still don't know what happened but I got better. It was stressful and it is perfectly understandable but the odds of you having one of those diseases is low.