Justin Bieber: 'It's Been An Amazing Week'

Access Hollywood
Justin Bieber at an autograph signing and fan meet and greet in New York City on June 19, 2012 -- Getty Images

Justin Bieber is on top of the world as his latest album, "Believe," climbs to the top of the charts - and the awe-inspiring experience isn't lost on the 18-year-old superstar.

"I feel great. I'm really happy," the teen heartthrob told Access Hollywood in New York City, ahead of his YouTube Q&A with Jimmy Fallon on Thursday. "The album turned out great and the fans love it and the critics love it and everyone's been raving about it. So, it's been an amazing week so far."

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With the album release, an appearance on "Late Show with David Letterman" and an NBC overseas special, is the superstar feeling the lack of sleep?

"No, I don't get tired - I'm actually a robot, so..." he joked. "No, of course I get tired, yeah. I get tired."

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The "Boyfriend" singer is handling the pressure though, keeping his focus on the wealth of opportunities he's been afforded and concentrating on his music.

"I'm pretty laid back," he said. 'I try to just take everything day by day and everything happens for a reason."

"Believe" - Justin's third studio album - is available in stores now.

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--Erin O'Sullivan

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