I have been having some pain in my right arm for a few weeks, and now it also moved to the back of my neck,maybe a pulled muscle .I know it hurts

Pinched nerve? Please have your doctor check this out. He/she might suggest therapy of various kinds or chiropractic. Please let us know what you do and that you're feeling better!

If you are youngish and in good health overall, I'd get a massage. Buy some ibuprofin. Take 400 mg every 4 hours.
Then see a chiropractor. (There are good ones and not so good ones.)
Think about how you sleep, sit at a computer, work. There are right and wrong ways to do all of those, and as you age, you don't get away with as much anymore!
Are you right handed, and do you use a computer mouse a lot?

Last, see a doctor. Truthfully, an MD just isn't going to do much. Especially if you haven't been through all the steps above.