Muscle spasm in neck /neck cramp question?

A few years ago I stayed in a caravan which was a bit chilly and woke up early morning to turn my neck when it spasmed and I had cramp in my neck. I have cramp quite frequently ( shoulder or legs) so I just assumed it would go but instead it cramped and I immediately had to go to the bathroom to be sick. For the next 7 hours I had to keep my neck as still as possible or else I would be sick every time I moved it even slightly I would be sick. I was fine to eat but it was quite painful swallowing. Obviously it wasn't anything serious due to it being ages ago, but out of curiosity does that normally happen with neck cramp or could it of been something else. I've had cramp in my shoulder at the bottom of my neck since, and various cramps but never do they have that reaction. It really terrified me at the time but we didn't go to the hospital.