Nick Jonas feels he knows "less" the older he gets.

Nick Jonas

Nick Jonas

The 25-year-old singer believes he has grown up a lot since he first shot to fame with his siblings in the Jonas Brothers in 2005, and sometimes looks back on his youth and thinks he was "so stupid".

He said: "I feel like the older I get, the less I know, whereas when I was young I thought I knew everything.

"Who you are at 15, 16, is a very different person from who you become at 21. Now, at 25, I look back and go, 'Ha ha, I was so stupid.' "

Nick is often recognised while out and about but is constantly surprised that people think he is "normal" when they spot him at a bar.

He added: "If I'm at a bar or having a drink somewhere like this, people look at me and they're so confused: 'You're so normal!' I want to know what their expectation was - that I walk in with a posse of, like, 50 people?"

The 'Find You' hitmaker knew his life was changing when the Jonas Brothers - who are also made up of his brothers Joe and Kevin Jonas - started selling out tours.

Speaking to American Way magazine, he added: "There was a moment when we put a tour on sale and it sold out in a couple minutes.

"I thought, 'This is beyond the point of no return.' It was like, 'Alright, cool, my life's different now. For the rest of it.' "

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