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ET has learned that Glee star Amber Riley collapsed during a cast screening and Q&A in Los Angeles on Tuesday.

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Amber later tweeted her fans, letting them know she's doing well, writing, "Hey guys, I'm okay :) I got a little dizzy from all the photog flashes! You'd think I'd be used to it by now, still a red carpet amateur I guess. Gonna get checked out but I feel fine. Thank you for all the concern and well wishes."

The cast and producers of Glee held the event for members of the Academy of Television Arts & Sciences at the Leonard Goldenson Theatre. Lea Michele, Matthew Morrison, Cory Monteith, Darren Criss, Chris Colfer and Jane Lynch were also in attendance.