Royal Wedding Cellist, 19, Asked by Meghan to Perform Had the Best (Hidden!) Seat in Chapel

Sheku Kanneh-Mason doesn’t tend to get nervous before a performance — even when that performance is at the biggest wedding of the year.

Nineteen-year-old Kanneh-Mason was one of the talented musicians who performed during Prince Harry and Meghan Markle‘s wedding ceremony on Saturday. Along with an orchestra made up of instrumentalists from the BBC National Orchestra of Wales, the English Chamber Orchestra and the Philharmonia, he played three songs during the Signing of the Register near the end of the wedding ceremony.

And despite the world-wide stage he performed on, Kanneh-Mason says he wasn’t very nervous before his performance. In fact, stage fright is something he rarely experiences.

“I was just very relaxed, and just soaking up the atmosphere,” he tells PEOPLE. “To have the opportunity to perform for so many people, I was just really excited.”

• It’s the event of the year! Be sure to keep up with all of PEOPLE’s royal wedding coverage and don’t forget to check out everything you need to know about Meghan Markle’s perfect style.

The 19-year-old cellist bowed out of a scheduled performance with the Los Angeles Chamber Orchestra on Saturday when he received a personal call from Meghan herself to ask him if he’d play at the wedding. Kanneh-Mason, who was named the BBC Young Musician of the Year in 2016, had previously performed for Harry at a charity event in 2017.

“I said yes immediately,” he says of Meghan’s out-of-the-blue call to ask him to perform. “It’s such an amazing event to have the opportunity to perform at. It was a surprise and such an honor.”

Playing for big crowds and television cameras isn’t new for Kanneh-Mason, who first rose to fame when he competed on Britain’s Got Talent alongside his siblings. But he says that playing at Harry and Meghan’s wedding was in another league entirely, particularly due to all the recognizable faces sitting in St. George’s Chapel, such as Oprah Winfrey, Priyanka Chopra, George and Amal Clooney, and of course, Queen Elizabeth.

“I’m definitely not used to playing at the royal weddings with famous faces watching,” he says. “That was something that was just such an honor — to get to perform for these people.”

Star-spotting highlights for Kanneh-Mason were Elton John, who performed at Harry and Meghan’s lunchtime reception — “It was really exciting to see him, and for him to hear me play,” he says — as well as David Beckham, as he’s a big soccer fan.

But of course, the ultimate sighting on Saturday was of Harry and Meghan. Ahead of his performance, Kanneh-Mason sat near the front of the church, off to the side, so he was able to “see everything that was going on.”

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When the time came for his performance, he played three songs: “Sicilienne,” “Après un rêve,” and “Ave Maria.” The first two were selections of Kanneh-Mason’s own choosing, while the last was at Harry and Meghan’s request. He says that he was “obviously happy” to play all three songs for the couple.

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Kanneh-Mason says that in the immediate aftermath of his performance, he was pleased with how it went, though he hasn’t had a chance to watch back yet. He says that he was told Harry and Meghan enjoyed it, too.

“I think to play at anyone’s wedding, is an honor,” Kanneh-Mason says. “But to play at a wedding of this significance, it’s just incredible.”

He adds: “They’re so lovely. I’m just so glad to have been a part of their special day.”