She’s sold millions of albums, and is now firmly one of Scotland’s most popular singers.

But Amy Macdonald always loves coming home to Glasgow – because she never gets recognised in the street.

As the Bishopbriggs singer releases her second album, A Curious Thing, this week, she explained why she’s happy to just be one of the girls when she returns home.

“I don’t get recognised anywhere – I’m just not that sort of person,” she laughs.

“If I was walking about dressed like Lady Gaga then maybe I would, but when I go out I look just like my friends, we’re just a group of 22-year-old girls from Glasgow. That’s the way I’ve always wanted it to be.”

Most 22-year-olds, of course, can’t say that they’ve hung out at an awards ceremony with U2 (they were lovely, according to Amy), topped the charts in Switzerland, Denmark and Holland or sold out the Barrowland Ballroom four times.

Amy has – thanks to her debut record This Is The Life being a smash hit when released in 2007.

Her distinctive booming voice, and ear for catchy melodies, quickly ensured that her star rose.

But although she’s busy getting her make-up done before our interview begins, Amy is still the same down-to-earth girl she was before her success.

And for the new album, it was returning home to Glasgow that inspired her to start writing songs again, after she completed a lengthy European tour.

“I’m not a prolific songwriter, I can’t lock myself away and come up with an album,” she says.

“So I thought it was going to be hard, but fortunately being at home, being with my friends and my family and just doing normal things was very inspiring to me. It then came together fairly easily, and it wasn’t the difficult second album everyone talks about.

“I just observe things, my friends, my family, watching telly – that’s where everything comes from in my songs.

“Glasgow is a diverse city and there’s so much going on, so there’s a lot of things to take from there.”

It’s certainly been a whirlwind few years for the singer, who’s now travelled all over the world promoting her first record.

But there was only one point when she let her emotions get the best of her – when she was devastated at hearing the news of the death of Michael Jackson last year.

“The one time I couldn’t control my emotions was when Michael Jackson died, and I was playing a gig the very next day,” Amy recalls.

“Seeing him at Wembley was the first concert I’d ever been to, and I was absolutely gutted – I wanted to play I’ll Be There at my gig as a tribute, but I just started crying after I introduced it.”

On a happier note, her new album featured another music icon, in the shape of the Modfather, Paul Weller, who played guitar and bass on two tracks.

However, it was a famous Scots actor, rather than a well-known musician, who inspired one of the record’s finest songs, An Ordinary Life.

“I got asked to the premiere of Gerard Butler’s newest film, as we’re close friends with one of his close friends, and she asked us along. It was really exciting – Gerard was lovely and said he had my music on his iPod. I didn’t want to hound him, so I thanked him and went into the background.

“But there were so many people who didn’t share that mindset – he was trying to chat to his mum, and every two minutes folk were wanting a photo and a 10-hour conversation about his life and their life. He did it with a smile on his face, but it made me think I couldn’t do that – I’m quite content to be ordinary.”

And Amy reckons that the album has benefited from her gigging experience.

“I’ve grown up a lot – some of the songs on the first album I wrote when I was 15, and people obviously change a bit in that time.

“I’ve played about 500 gigs, and that live rockier sound has come across more on this album.”

While Amy’s Scottish fanbase are obviously eager to hear the results of the new record, she’s gained a devoted European following too. That’s led to the singer playing some of her biggest shows across the continent, an experience which she confesses can sometimes be quite awe-inspiring.

“In places like Germany and Switzerland I’ve been playing places the size of the SECC, if not bigger – I did a show in a market square in Locarno, and in the background I could see the Alps, and there were 12,000 people singing my words back to me.

“It was at times like that I get so emotional and I have to fight back the tears, as I feel don’t deserve this.

“I know I’ve put in a lot of hard work, but I know I’m fortunate as there area so many amazing bands out there who haven’t had that level of success.”

She’s also a fan of several modern pop acts too.

“I’m a fan of Lady Gaga, she’s really cool and really different – I think she talks a lot of rubbish sometimes though! But she’s very cool, and writing her own songs, which to me is a big deal.

“But I have liked some of the recent X Factor acts too – JLS are phenomenal and that’s fine, because Britain needed a good boy band.”

And though the singer admits that there are hardships to life on the road, there’s no way she’ll moan about them.

“I only whinge about any problems being on the road to my band – if I started moaning about it in public I’d look like an old bag!

“There are loads of people who have much harder lives than me, so I won’t moan about that.”

• Amy Macdonald’s new album, A Curious Thing, is out now.