Taylor Swift made a surprise appearance to the Billboard Music Awards! It's a good thing too, since she scooped up Best Female Artist, and Top Selling Artist! However everyone is talking about the video Darren Criss uploaded to his twitter during Shawn Mendes's performance. Taylor Swift and Camila Cabello were the only two people standing up during the performance and they were right in front of Darren Criss so he documented the moment. He failed to get Taylor's attention to sit down. LOL My advice, better stand up if ya wanna see him dude!!