Jessica Simpson hard drinking, period 3 weeks late

Simpson asked was rushed to Cedars-Sinai Medical Center in L.A. on March 28 and remained there for four days. Reps for the singer said she was being treated for a "kidney infection," but an insider tells Star it was more than that. Jessica's health problems were "brought on by drinking an obscene amount of alcohol," says the source. "She was treated for a kidney infection, a bladder infection and a urinary tract infection."

Adding to her distress, anxious Jessica asked doctors to give her a pregnancy test! "She was a nervous wreck," says the insider. "She was three weeks late and convinced she was pregnant. She was feeling really weak and really scared. She was unraveling."

"She used to keep her drinks to a minimum, because she's very conscientious about the calories," says a source. "But Tony and his buddies really party hard, and I think they expect Jessica to keep up with them. But she is like a third of their weight and just can't hold as much as they can."

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