An ambulance was called for Frankie before he took the stage after he became shaky from having not eaten all day, the singer revealed.
"I ate a whole bag of those red candies, and all of a sudden 20 min before the show, I get the shakes," Frankie told Access Hollywood's Billy Bush on "The Billy Bush Show" on Thursday.
"[The paramedics] took my blood pressure and asked me questions and all that stuff," he continued.
But Frankie told the emergency medical team that the show must go on!
"I said, 'Hey, I am on in five minutes!' And of course, I did the show and everything was fine after that," he added.
Despite his medical scare, Frankie turned out a stellar performance – even making judge Simon Cowell smile.
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