There is a voice.

It swells up, deep and mournful, through the humming keen of the guitars and sits above the submerged boom of the drums demanding all your attention. To hear it is to feel its narcotic, erotic, melancholic pull. The ache and doomy swoon of it.

And then there is another voice. It sings down the phone, constantly amused, cackly even. It is telling me about boyfriends and dancing and eating kebabs in Berlin yesterday. "They have the best Turkish food in Germany," it says.

You have already worked out the twist in this tale, right? You already know that these two voices are one and the same.

"Teddy! Hello love. Are you alright?" Nadine Shah says when I call in a voice that's all warm and Geordie and a Northumbrian country mile away from the one you'll find on her new album Fast Food. In conversation Shah is funny and flighty and full of beans. On record - as anyone who has heard the singles Stealing Cars (a late candidate for single of the year in 2014) or newbie Fool can attest - she sounds either heartbroken or a heartbreaker.

Fast Food is an album of rich and next-door-to-Gothic love songs that ring and shiver with all the mess and murk that gathers in the human heart. They're songs about anxiety and pose and a twentysomething sense of things coming apart. You can read into the title Shah says. "Yeah, the album's kind of about a succession of really intense and short-lived love affairs. It's a metaphor for that."

Are you suggesting that your twenties have been a tumultuous time, Nadine? "They have. I'm nearing the end of my twenties. I'm clinging on to them. But it's a funny old age. I'm really quite reflective. The older I get, I'm looking back a lot on certain relationships and periods of my life thinking 'Oh, I was very immature at that point and very unkind here.' I think the older you get, you meet people who have been in love before and you discuss past loves and that's at the forefront of your mind when you meet somebody else."

Love is never first love any more at her age, she says. Is that a problem? "Well, it was for somebody who's quite a paranoid, jealous person." And that was you? "It was. I'm trying to battle that because it's just ridiculous. Meeting somebody in their late twenties, early thirties, who hasn't been in love before... That rings alarm bells now. You think 'What the hell's wrong with you?'"

She worries aloud that love songs might be past their sell-by date. "It's a tired old subject, writing about love."

But we all seek it, Nadine. "Yeah, it colours in the boring parts."

Who was her first love, I ask. She bursts out laughing. "He was a musician and I can't tell you his name because he's a little bit famous. A political singer-songwriter."

What went wrong? "I think I was just a crazy person. I think I went wrong. It was definitely my fault. With anyone who is very career-driven, it can be very hard to have a relationship. But if you get two of them... two people who are very passionate about what they do..."

Lots of fights and sulks over the pizzas? "Yeah, all of that. 'Your song's s***.'"

The Nadine Shah story goes like this. Brought up in the seaside town of Whitburn on Tyneside, the daughter of a Norwegian mum and a Pakistani father, she grew up listening to Buddy Holly (her mum's favourite), her brother's Jimi Hendrix records and imbibing her father's love of Nusrat Fateh Ali Khan. As a teenager she loved Mariah and Whitney. (She still does; "I was listening to Mariah Carey's Honey the other day. Her new stuff is terrible though. So upsetting. I don't like the new Mariah.")

But it was discovering Nina Simone that changed things. As a result she moved to London, became a jazz singer. Now she has reinvented herself again as a singer-songwriter who you might place in the same ballpark as PJ Harvey and Anna Calvi. But she remains her own woman. And if you listen closely enough to her singing voice you can hear the Geordie in it.

Fast Food is her second album. Her debut Love Your Dum And Mad came out in 2013, marked her first collaboration with producer Ben Hillier ("Ben and I are going to be working together until one of us croaks it," she says.) It comes in an album that's blood red in colour. Nadine, it looks very much as if you've had your throat cut on the cover. "Yeah. It looks like that, doesn't it? I'm really regretting that now. Uh... the thing is with this artwork, I wanted it to be bold and very vivid and simple. Three bold colours. Green, blue, red. I wanted femme fatale characters and I was looking at Italian 1970s horror movies. Those kinds of images. That's what the artwork is meant to be referencing."

Does she have the odd femme fatale moment herself. "Possibly. Now and again. I think it's nice to adopt different characters. If you listen to the lyrics on this album it's all from personal experience. But we have artistic licence. We do exaggerate. It's good to adopt those characters for that purpose. Otherwise you just get a comical Geordie, which isn't as attractive, I don't think."

Random questions for Nadine Shah inspired by the lyrics of Fast Food.

What's your mum's definition of classy? "Not me!"

Have you ever stolen a car? "No, I can't drive."

Do you get bored easily? "Yes. I have a very, very short attention span. I have chronic anxiety and apparently it's something to do with that. Stealing Cars especially is about my anxiety."

She's in a better place now, she says. Cognitive Behaviour Therapy seems to have helped. But she's always been attuned to the fragility of our mental states. Her early single Dreary Town was inspired by a boyfriend who committed suicide. She knows what life's darker colours look like.

And yet she likes to dance and, if you heckle loud enough at her gig at King Tut's this month, you never know, she might even rap for you. "I'm dead good at dancing and even better at rapping. I'm not joking. I'm really good at it."

Right now though she is knuckling down and writing. There's always a new song, a new album to work on. "And there is a new side project I can't say who with yet."

All of which, she says, is part of justifying what she does as a proper job. Because it wouldn't take much for her to just sit in front of the telly all day, she admits. "I'm very lazy. It's a talent how I can waste a day doing pretty much nothing. If I have days off I have to force myself to write."

What is your guilty daytime TV pleasure then? "It's really bad. It's called Say Yes To The Dress. Oh my God. Wedding programmes. I love them. Don't Tell The Bride. Four Weddings. Say Yes To The Dress and I Found The Gown. I'm getting to the age where I'm wedding broody. Never mind the man, I just want the party and the dress.

"My brother had a massive Asian wedding and it has to trump his. It was on Park Lane. He's the eldest son and the first to get married and it was massive. There were about 400 people there. So it's going to have to be up north somewhere because I can't afford London... And I'm going to have to have elephants. Honestly."

Fast Food by Nadine Shah is released on April 6. She plays King Tut's in Glasgow on April 13.