3. Katy Perry
Katy was performing live, singing her super hit song, 'I kissed a girl,' when she decided to jump in the air. What she hadn't planned was that she would dive straight into a huge pink cake kept in front of her. But if you thought that was embarrassing, guess what happened next. She had to perform in that cake-stained dress for the rest of the show!
4. Britney Spears
While performing in front of a sold-out crowd in Las Vegas, Britney Spears had yet another embarrassing moment when she made a sudden head movement, throwing her hair extensions right across the stage.