I guess it could be a trapped nerve -they can be pretty painful, - I had a really stiff neck and pain in my shoulder and top of spine and went to the doctor last week - he said I had 'a severe muscle spasm' - whatever that might be!
Anyway he has given me anti inflammatories, - I've got naproxen with I think is only on prescription, but I'd say go for something like ibuprofen if you can take it without stomach problems, - if not go to the GP. (I get stomach problems with anti inflamms, so I get given lansoprazole to take with it - to protect the stomach.)
Or you could try rubbing in some ibuprofen gel if you have any, or even some deep heat if you have that - they might help.
Good luck - a pain in the neck is -- um -- a pain in the neck
I've got spondylitis. It sounds similar. Mine only plays up when I've been lifting stuff or slept strangely. I use anti inflammatories and, if it's really bad, a diazepam. Probably out of date since I've had a the strip for about five years.