The 19-year-old singer took to the stage at the Royal Albert Hall to celebrate the monarch's 92nd birthday on Saturday (21.04.18), and has admitted that the royal crowd - including the Queen herself, Prince Charles, Duchess Camilla, Prince Harry, Meghan Markle, and Prince William - made him more nervous than he had anticipated.
When asked if he'd managed to meet Prince Harry, 33, and his fiancée Meghan - whom he will marry on May 19 - Shawn said: ''I didn't [meet them], I actually chickened out. I walked by the hallway and I saw them in there and I was like, 'Should I go say something? Nah.'
''Usually I don't freak out like that, but I was really ... I was surprised by how nervous I got in front of them.''
And the 'In My Blood' hitmaker even admits he was more nervous about the thought of meeting the younger royals than he was when he spent ''15 minutes'' stood next to the Queen before he went on stage.
He added to 'Entertainment Tonight': ''I stood next to the Queen for about 15 minutes, waiting to go on stage. We didn't technically meet, but I was standing next to her. It was really awesome! It was a lot more relaxed then I thought it would be, in the best way. That was just - truly, I'm having a really great week.
''She's very funny. The whole royal family is very normal and just, like, super likeable and amazing.''
Shawn also told the publication that whilst he hasn't been given an invite to Harry and Meghan's nuptials, he will be watching the televised broadcast ''like everyone else''.
Queen Elizabeth's 92nd birthday celebration was attended by several royals, however Prince William's wife Duchess Catherine was noticeably absent from the show, as she welcomed the couple's third child - an as-yet unnamed son - into the world just two days later on Monday (23.04.18).
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