DUFFY has lost count of how many interviews she's done today. This one could be about her "95th", she jokes.
Despite the hectic schedule during her brief visit to Australia, she's managing to sound bubbly and upbeat. (Her secret is loads of fizzy drink, she reckons.)
Last year was a big one for the Welsh pop starlet, who was born Aimee Ann Duffy and grew up in a tiny dot of a town called Nefyn. It was the year her debut album Rockferry, four years in the making, was released, becoming one of the biggest-selling albums in the world; the year she was nominated for many awards including this year's Brit Awards, inspired countless newspaper articles, travelled the world, including touring the US with Coldplay, and turned 24.
When Rockferry was released in May, it went straight to No. 1 in the UK, where it was the highest-selling record for 2008. (It reached No. 4 in the US and No. 2 in Australia.) Rockferry was the fourth-highest-selling album in the world (behind Coldplay, Amy Winehouse and AC/DC), selling more than 4.5 million copies.
But for Duffy, 2008 was a year like any other on her continual learning curve. "Ever since I left home I've had this big year of colossal learning, so it just felt like another one of those whirlwind experiences for me," she says.
Duffy's speaking voice is light and relaxed – but becomes a powerhouse when set to music. When she was a child, she was kicked out of the choir because her voice was "too big". She got her taste for soul music from watching her dad's VHS tapes of '60s music show Ready, Steady, Go! and reruns of the movie Sister Act.
Meeting Whoopi Goldberg on a chat show was one of the highlights of her year.
Last year she also performed at a charity event with stars including Mariah Carey and Rihanna. Stevie Nicks of Fleetwood Mac was fun – entertaining her with stories on Welsh dragons. But small-town girl Duffy wasn't impressed with some of the other star's big entourages. "I don't like how big American stars consider themselves an exception from humanity," she said then.
Nefyn, in north Wales, is on the Llyn Peninsula where Welsh is spoken. Duffy's parents ran the community centre. Her first language was Welsh, which she spoke at home with her two sisters, one her twin. When her parents split up, it became community news. Her mother left to follow her heart with a former flame, taking the children with her. Duffy eventually left to live with her dad, which caused a rift in the family for a while.
She always knew she wanted to sing, though, jotting down lyrics whenever she could. She still carries her notebooks with her.
"I'm never short of a pen and paper, so I try and catch my moment when I can."
It was record label Rough Trade that finally spotted her talent and she was introduced to Bernard Butler, former guitarist with '90s indie band Suede. He fleshed out her musical knowledge, loading up her iPod with songs she would listen to on the long train journey home to Wales from the label's London studio.
Butler pushed her to her limits. For example, he asked her to sing the title track Rockferry up by a fifth. "Do this or go back to Wales," he told her.
"I think he'd love to take that claim to fame that he had the audacity to say that to me," says Duffy. "But no, it wasn't anything quite as drastic as that. But he was scaring me with the amount of movement he was making in the chord progression.
"He's a real gentlemen, you know. He's gotten himself into a little bit of trouble in interviews. He doesn't take any shit. But that's what I love about him. He knows what he wants and he goes and gets it in life. It's wonderful to be around him."
The same can be said of Duffy. In interviews she comes across as a real straight-talker – not a wide-eyed innocent. If she hasn't wandered down the dodgy paths of fame, it's because she has already seen the harsh realities of life close up.
Duffy may not have had the biggest record collection, but music is a big part of her daily life. She falls asleep to classical music.
"There's a song I like called Clair de Lune," she says. "So I put that on. And I always have the radio on in the house. I always love to have a great moment when your favourite tune comes on and you crank it up for a moment while you're having a glass of wine or something.
"I think a house has to be filled with music. It always has to have a fire. My grandmother used to say that when there was a fire burning you'd never feel alone."
A song she'll turn up is something like Aretha Franklin's I Say a Little Prayer.
"That's like a total real moment on radio, you're like, 'Oh, hello! Thank you!"' she enthuses.
"I'd probably crank it up and go, 'Wow! How amazing is this?"' she says. Life is still full of pinch-me moments.
When Duffy next returns to Australia it will be to play the V Festival, alongside The Killers, The Kaiser Chiefs and Snow Patrol.
Neither ostentatious nor shy, Duffy is handling the hot glare of the spotlight well. A year of British media attention has taught her that the attention doesn't turn off when the song is over.
"I think that the hardest thing was letting go of the fear," she says. "You know, understanding that there's no point in being afraid."
But there were points when Duffy did start to feel the cracks. At a show in New York, 20 minutes into an otherwise-confident set, she burst into tears.
She doesn't know what made her cry – only that at one out of every 15 shows she tends to get emotional.
Is success all she dreamed it would be? "I don't know yet," she sighs. "I need probably a little bit of time to reflect, but yes, it's definitely good fun at times."
She says the best thing about it is: "The fact that you're always challenging yourself. You're always trying to understand yourself."
And the worst thing? "You're always challenging yourself and you're always trying to understand yourself," she repeats. "It's a double-edged sword."
As for what makes her happy, the answer is a one-word reply: "Peace."
"I think every morning you wake up and you feel so peaceful and relaxed. And then the day starts and you suddenly get flurried with worries and phone calls."
Rockferry deluxe edition is out now. Duffy performs at the V Festival, Gold Coast, on March 29; ticketmaster.com.au