Did Niall have an onstage nightmare?

During a performance at the Apple Music Festival, fans were shocked when Niall Horan ran off stage, leaving the other three boys to perform without him. "Where's Niall?" Louis asked, with Harry adding, "We've lost another one!" So, what happened? It turns out that Niall had gotten sick mid-performance and needed a breather. "He just developed a sudden sickness," Liam told the crowd. And by the time Niall made it back onto the stage one song later, fans feared he would have to be taken away in an ambulance. But Niall made sure to clear the air! "There was no ambulance, don't worry," he said. "I just overheated on stage and didn't feel well!"