There was a time when I would have a stiff neck on two days, on average, every week. Couldn't figure out why. I believe that last February and March, I had awful neck pain that lingered for two months until I got so exasperated by it, I just applied a heat patch on it everyday for a week.
My problem was susceptibility to stiff necks for an extensive period of time but they pop up at random and seldom do they pop up. Maybe your problem is worse than neck stiffness.
One thing I liked about having a stiff neck though was that gave me a valid excuse to ask my last ex to massage my neck and shoulder stiffness for like an hour everyday. Man, was she a great masseuse.