03/02/2013 01:30 EST | Updated 03/04/2013 11:19 EST

Justin Bieber's Birthday The 'Worst,' Singer Tweets As He Turns 19 (UPDATED)

UPDATE: Justin Bieber took to Instagram Sunday to explain his “Worst birthday” tweet after reports that some of his underage party guests were denied entrance to a London club to celebrate the occasion.

“The funny moment when people believe I brought underage people to a club,” he wrote. “I love how the club wanted to give the press another reason why we didn't stay at their weak-ass club so they wouldn't look bad for me walking in and right back out. I said ‘Worst birthday,’ but that was due to dummies pushing over my fans and being overly aggressive.”

Justin Bieber’s birthday was apparently kind of a bummer. After turning 19 on Friday, the Canadian pop star tweeted the message "Worst birthday" to his followers.

His tweet may have had something to do with the circus-themed bash at the London Cirque du Soir nightclub, where a disagreement between Bieber’s people and the club’s staff reportedly broke out over some underage party guests, according to the Daily Mail. His guests included rumoured girlfriend, 17-year-old British singer Ella-Paige Roberts Clarke, and 14-year-old actor Jaden Smith.

The Twitter hashtag #BeliebersHatePaparazzi is also trending, suggesting they may have contributed to Bieber's bad night.

That same day, his friend Lil Twist was pulled over yet again for making an unsafe lane change while driving Bieber’s Fisker Karma in Los Angeles, TMZ reported. Lil Twist was previously pulled over in Bieber’s Ferrari in January, and another car stuck and killed a paparazzo attempting to take photographs.

Whatever the cause of Biebs' birthday angst, can you blame him for venting on Twitter?

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