Balls were jingling! At the annual iHeartRadio Jingle Ball in LA, some of the biggest names in music serenaded the crowd into the holiday spirit, despite the super-warm temperatures Cali!

Kesha, Demi Lovato, Sam Smith and more took to the stage for one of our favorite events of the year -- and TSwiz was there, too, folks. In fact, we caught her mom getting left behind by a chauffeured SUV -- dude had to throw it in reverse to go back and pick her up! Wonder if Taylor Swift was in there yelling at the driver!

Master of ceremonies Ryan Seacrest was being chauffeured as well, but in a golf cart. He had to work -- no time to relax for Ryan! The hardest-working-man-in-showbiz was recently accused of sexual harassment by a former employee but the accusation hasn't brought him down ... particularly when reports emerged that his accuser had tried to sue for millions before she came forward with her story. Hmmm ...

Meanwhile, we caught up with Kesha after the big event, hopping a plan out of LA, when we were able to congratulate her on her Emmy nomination ... I mean her Grammy nom -- watch!