"Idol" champ Jordin Sparks cancelled three shows over the weekend, and the reason might be a throat injury that could be really serious.

Sparks had to ditch gigs in State College, PA and D.C. because of "an acute vocal cord hemorrhage" –- shudder -- and according to Penn State arena officials, she was ordered to "strict vocal rest and will not be able to perform anywhere until her condition improves."

Her reps could not be reached yesterday.