Oh my god, when Beyonce came out, you could feel it," she told ET backstage after the performance. "It was electrifying. The place went nuts. It was like shaking, like, it was so insane -- and I was excited as a fan, too. Like, I was excited that they were about to experience this, because both of our fans have been threatening us online, saying that if we didn't perform together, they were going to hunt us down.