5. LOSES HIS BREATH, THEN HIS SHIRT AGAIN
Suffering breathing problems throughout a March 7 show, Bieber collapsed on stage at London's O2 Arena, sucked down some emergency oxygen backstage, then came back to finish his performance before being whisked to the hospital. There, he Tweeted another photo of himself shirtless, blaming his ordeal on the paparazzi and vowing to "get focused" and return to the stage. "Not gonna let them get the best of me again," he wrote.