We have no way of knowing whether Justin Bieber picked up a bug or simply partied too hard the night before his big Believe Tour kicked off in Arizona on Saturday. (The story as tweeted by Biebs? “Milk was a bad choice! Lol.”) What we do know, thanks to a YouTube video offering the “BEST VIEW,” is that Bieber headed to center stage, turned his back to the audience, and yakked in the middle of a song. No one said being a Belieber would be pretty.