What Causes Recurring Pain In The Neck With Headache?

I have been experiencing intermittent neck pain. It comes and goes. The right side of my neck will start to hurt and as soon as the neck pain starts, I then begin to get a pain in the top of my head. This lasts for just a few minutes (5), goes away, and then returns several minutes later. I don't think this is a pinched nerve, because the pain is not constant. What could this be??