Do you know the feeling when you eat ice-cream too fast and you get a sudden, very painful headache? It's called sphenopalatine ganglioneuralgia and it is caused by the sudden dilation of blood vessels in the head.
Luckily, I haven't had this feeling since childhood. I hated it back then. You cannot do anything, but to wait for it to go away.
Ice-cream hell. :)