Okay this literally just happened to me. And it has happened before. I have been dieting lately. I woke up at 10AM and just decided to eat a sandwich. I got the cramp on the roof of my mouth. Exactly how you guys have explained it. I tried to stop eating after that first bite. It continued. So I decided to just keep eating the sandwich. And the cramp subsided. This is a hilarious symptom I’m my opinion and very interesting that so few people know or talk about it!!!