She may only be one bench press away from becoming an actual bionic woman, but even Madonna feels the strain now and then. The singer sensationally collapsed on stage in Sofia, Bulgaria this week, and later during the show passed out as she walked backstage. It happened as her Madgesty was singing Holiday, and she simply fell back onto one of her backing dancers, seemingly unable to wake up. Scary stuff. She managed to pull it together a few seconds later, but insiders say she was seriously worried about it after the show. "She is suffering from exhaustion," claimed one source. Madge was advised by doctors to postpone her next few gigs, but the stubborn singer has refused. Watch the moment Madonna came over all dizzy above, and then tell us your thoughts.