Most people have dreamed of joining their favorite artist on stage, but one Lady Gaga fan who was picked to help her out with a song at her Thursday night concert is probably wishing it never happened. The star invited a fan called Jack to join her on stage and jumped into his arms, then he almost immediately lost his footing and both plummeted to the floor below. “We legitimately thought she was dead,” one audience member wrote. Fans were concerned because Gaga lives with fibromyalgia, an arthritis-like condition that can impair the joints. However, she shrugged it off as security guards helped her back up: “Everything's OK ... The only thing that's not OK is we need some stairs for the damn stage so I can get back up,” she said. Gaga also consoled Jack who burst into tears, asking him: “Could you promise me something? Could you forgive yourself right now for what just happened?” She then played Million Reasons with Jack at her side.