Louis Tomlinson's fans are freaking out!
See some of their concerned reactions (below):
[Image via Splash News.]
Oh hey, Becky G!
Thanks for fillin' in on such short notice!
Coming in as a ringer was this young musical act that the teens just seem to love!
Ch-ch-check out the video (above) and enjoy her last-minute, but in it to win it performance of Shower!