Justin Bieber is ''a mess'' without Selena Gomez.

The 19-year-old singer split from the 'Love You Like A Love Song' singer in January after almost two years together and Justin's friends fear he is spiralling out of control without her.

A source told In Touch: ''He misses her. His friends are a terrible influence and they're with him nonstop now. Justin's out of control. He's going down a bad path.''

However, Selena, 20, is thriving since the split and has being spotted out on the town with her close pals Vanessa Hudgens and Ashley Benson.

The insider added: ''Selena's in a better place and doing fine without him.''

Justin is lying low after a rough week in London, where he angered his young fans by rocking up almost two hours late for his gig at the O2 arena.

He also ranted about having the ''worst birthday ever'' when his underage friends weren't allowed into a club for his 19th celebrations, and rounded off the week by attempting to fight a photographer in the street.