Just ask British icon Daniel Radcliffe!
The only problem??
Just look at their sad, sad faces!!
Ch-ch-check out the clip to see Anna & Justin's priceless reactions (below)!!!
[Image via itv.]
This girl is having one heckuva year!
The Grammy-nominated singer performed her hit Boom Clap, which was a little more toned down than the radio version, but still ferosh!
Then Break the Rules was next, which was the more lively of the two, and included lots more dancing from the singer!