At a concert in Glendale, Arizona on Saturday, 18-year-old teen phenom Justin Bieber took ill onstage and vomited twice during the first night of his 'Believe' tour. Maybe Beebs finally heard his own music and couldn't stomach it? (Sorry, Beliebers, we couldn't resist.) The video is NSFW, by the way, due to Bieber barf.

During a performance of 'Out of Town Girl,' Bieber pauses, turns his back to the audience and forcefully vomits while hunched over. Then, he makes a quick dash offstage. His backup dancers, meanwhile, continue without missing a beat. Later, Bieber returned and asked the audience, "Will you love me even though I’m throwing up on stage?"

According to Bieber, he vomited due to nerves and drinking too much milk. "And .... Milk was a bad choice! Lol," he tweeted. Despite his upset stomach, however, Bieber was able to complete a 21-song set. What a trooper!

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