Amy @ Lollapalooza

"Amy was admitted to London's University College London Hospital for exhaustion, treated and released just this afternoon," the singer's rep, Tracey Miller, tells PEOPLE. "The doctor said she was suffering from severe exhaustion, and she was told to rest."

"Amy has been pulled in a million directions," added her rep. "She has done hundreds of shows and promotional appearances in the last year, often working 16 hour days. It's bound to catch up with anybody."

Don't Shoot the Messenger

Which troubled, hard-partying Lollapalooza performer cleared out a bathroom over the weekend in Chicago and then smoked what our spy-in-the-stall swears was a crack pipe?

Labels: Amy Winehouse