If you were following Mix 103.7 on twitter (www.Twitter.com/Mix1037), then you already knew yesterday that the girls and guys were flip-flopping their performances on American Idol... if not, you were probably pretty surprised. All producers would say was that there was there was a "medical scare" ... so what happened??

Turns out contestant Crystal Bowersox had complications related to diabetes and her doctors said she could not perform last night. So the producers had the guys perform last night and the ladies will take the stage tonight. We are told Crystal has been practicing for tonight and will take the stage as long as she's cleared by her doctors later this afternoon.

Hope she feels better soon!