Last week I went to my friends' band's (Throne of Bone's) last show; it was on a Wednesday. Thursday's bangover was bad, I could hardly lift my head. Friday was actually worse. I think now that my hair is a little longer and I'm less practiced at metal-show-going, my neck is more easily affected by head-banging.
Bangover is actually a well accepted term within the metal scene. Here, see for your self, though there is a little confusion on Urban Dictionary.
Also, here's a song all about bangover: