Demi Lovato Rocks Y100's Jingle Ball 2013

Demi Lovato hits the stage during Y100′s 2013 Jingle Ball held at BB&T Center on Friday night (December 20) in Miami, Fla.

The 21-year-old singer tweeted ahead of the show, “So excited for the show tonight…. #jingleball2013 #NEONLIGHTS.”

PHOTOS: Check out the latest pics of Demi Lovato

Earlier in the week, Demi made the announcement that she was leaving her post as a judge on X Factor.

She wrote after the finale, “Last night of the XF for me!! I had a great time but I can’t WAIT to tour for you guys!!!”

15+ pics inside of Demi Lovato…