Singer-songwriter Ed Sheeran spent his Monday afternoon meeting Queen Elizabeth II and performing for a billion people. Not bad for a 21-year-old who was largely unknown just a year ago.

Sheeran sang at the Queen's Diamond Jubilee Concert as part of a celebration to recognize Queen Elizabeth II's 60 years as the head of the British Royal Family. At some point before or after the performance, Sheeran had a chance to shake the queen's hand.

"So apparently 1 billion people are tuning in tonight. No pressure then," Sheeran tweeted just before the concert. As he typically does, Sheeran took the stage alone with an acoustic guitar. While attendees waved the British flag, Sheeran sang 'The A Team,' a song about a homeless woman addicted to hard drugs. That's heavy subject matter for such a celebration, but 'The A Team' hides its serious storyline in metaphors about angels flying, so we're guessing the 86-year-old queen wasn't offended.

'The A Team' was Sheeran's first hit in the U.K. and remains his highest-charting single. It appears on his album '+,' which will be released in America on June 12.

Watch Ed Sheeran Perform 'The A Team' at the Diamond Jubilee Concert