INGLEWOOD, California (AP) ― The rising pop-rock band 5 Seconds of Summer gave its feverish female fans the surprise of a lifetime by personally selling tickets Saturday morning for an upcoming concert in Inglewood, California.

Many fans, including 13-year-old Trina Umana, camped out overnight at The Forum to get seats for the Australian group’s first U.S. headlining concert on Nov. 15.

“I can’t speak right now. I’m too overwhelmed,” she sobbed after purchasing her tickets from guitarist Michael Clifford, 18.

Before heading into the box office, drummer Ashton Irwin, 20, said his only concern was the group’s math skills.

“We might lose track of a lot of coins and stuff like that. But we’ll work it out. We’ll get through it,” Irwin joked.

Maria Gomez certainly wasn’t paying attention to the numbers.

“All I could think was: ‘Oh my God. I don’t know what to do. Don’t embarrass yourself!’” said the 15-year-old fan from Anaheim, California. “None of us thought any of this would happen.”

The quartet, which also includes lead vocalist and guitarist Luke Hemmings, 18, and bassist Calum Hood, 18, can relate to the fandom.

“We’re more awkward than anything,” said Irwin of meeting artists he admires like Fall Out Boy bassist Pete Wentz. “But inside, when they leave, we sort of squeal.”

Green Day, Blink-182 and Imagine Dragons also top their list of musical influences.