The intrepid Ed Sheeran, on proving them all wrong

Ed Sheeran is one of the most popular performers on the planet. His music videos have been viewed on YouTube nearly half a billion times. But Sheeran said it wasn't so long ago that he considered himself just a weird kid with huge glasses, a stutter and pale skin.

Now, he's a phenomenal one-man show, reports CBS News correspondent Anthony Mason.

The ginger-haired troubadour was just 16 when he quit school and took off for London to launch his music career.

"It wasn't so much confidence; I was very surprised at how many people actually thought it wasn't gonna work, and no one said anything," Sheeran said. "The whole time I was like, 'Yeah, I can do this. Everyone's behind me. Everyone's down with it.' And then when it happened, everyone was like, 'Blimey, I didn't expect that to work.'"

It's working alright. At 23, Ed Sheeran, Teddy to his friends, has sold more than 24 million singles and albums. Spotify named him the most streamed artist in the world last year.

Just five years ago, he couldn't get a recording contract.

"You should have seen me back then. That's the thing. It's all well and good looking back now and saying 'Oh, it's just like the Beatles, everyone turned them down,'" Sheeran said. "I looked strange as well. I'd drunk too much beer and ate too many fries. I wasn't fat, I was just round and shiny."

One old manager even suggested a new hairstyle.

"It wasn't technically 'dye my hair.' He said it a bit more politely: 'Maybe just get some blonde streaks,'" Sheeran said.

He busked and gigged wherever he could, playing more than 300 shows one year, while he sofa-surfed, sleeping on friends' couches.

Then in 2011, his song "A Team" finally broke through in Britain. Taylor Swift heard his music the next year and asked him to open for her.

"What it did do was it made me a household name within six months because I had the Taylor Swift brand of approval," Sheeran said.

Soon he was selling out shows, three nights at Madison Square Garden. This summer he'll play London's massive Wembley Stadium, his biggest solo shows yet. Over 80,000 fans in three nights -- that's a quarter of a million people.

"It's just happening and it's weird," he said. "I want to do it cause it really messes with people's heads."

It messed with Noel Gallagher's head, the outspoken guitarist of the rock band Oasis said last month that he "can't live in a world where Ed Sheeran is headlining Wembley."

"I love it when he slags people off, and I just happen to be one of those people," Sheeran said.

It doesn't bother him though. After all, he said, he's playing at Wembley three times, and the top artists in the world want to collaborate with him. Pharrell Williams went into the studio with Sheeran for his latest album "Multiply."

"I kind of walked in and didn't really know what he was gonna do," Sheeran said. "And his like, opening thing, was just, 'You seem like James Taylor and like Joni Mitchell. They singa-songwriters. You a singa-songwriter, too. But they ain't never made nobody dance.'"

The Pharrell-produced record, "Sing" would be the first hit off the Grammy nominated album. It's the third straight year Sheeran's been nominated, and he's hoping to add another tattoo to his well decorated arms.

"I've saved a space here for the last three years to get something related to the Grammys. But every single year, there's just a massive gap there - hopefully," Sheeran said.

Sheeran said the Grammys are important to him and while some Oscar-nominated actors say they're just honored to be in the running, he said that's not the case.

"You're not. You're not just honored to be there," he said. "You're going to win. That's why you go. And if you don't win, you're going to be pissed off."

Sheeran remains remarkably focused and driven for someone so young. He said when he's sitting among his peers on Grammy night, he'll be looking around thinking "that's my competition."