It's official: Justin Bieber and Kim Kardashian aren't dating. In fact, they never were. But his fans thought otherwise and freaked out. It all started at the White House Correspondents Dinner last Saturday, when Justin Bieber, 16, tweeted a photo of himself posing with Kim Kardashian, 29, with the message, "Look, it's my girlfriend!" Moments later, Kardashian tweeted back, "I officially have Bieber fever!!!"