Yup exactly this!!if you turn your head to the side, does it hurt/can you feel the muscle pulling?
if so, I can't remember the name of the muscle, but it is essentially a small muscle that is going to spasm, what is happening is that the larger muscle that should do the work is either tiring or not being used properly, so your body uses the small muscle that tires very quickly then spasms. It is horrible I used to get it all the time from rugby.
Dumbbell over head press to build up the bigger muscles so the smaller one doesn't get used is the best way around it, doesn't have to be heavy, just train it up