Oh dear.

Lady Gaga is newly engaged to Vampire Diaries star Taylor Kinney, after meeting the heartthrob on the set of her music video “You and I”. Taylor popped the question with a stunning heart-shaped diamond ring on Valentine’s Day. Magical.

But just as the couple prepare for wedded bliss, an explosive interview from the Daily Mail alleges that Taylor Kinney was already in a relationship when Gaga started dating him.

Lady Gaga and Taylor Kinney.

That's when things get tricky.

Taylor Kinney's ex-girlfriend Brittany Sackett has come forward to tell the world that she found out he was seeing Lady Gaga after he accidentally called her while... uh... hooking up with Gaga.

I know, confusing.

She answered her phone at 2.30am, only to hear kissing sounds and the muffled voice of superstar Lady Gaga. She was shocked to say the least.

"Taylor pocket dialed me at 2.30 in the morning. 

I could tell it was intimate conversation, I could hear kissing, muffled sounds and I recognised Lady Gaga’s voice," she says to the Daily Mail.

Probably not as shocked as Taylor was when he realised what he'd done and called Brittany the next day. Without an explanation.

"I wanted to see how it played out, but later I saw one of his friends and he said to me, 'You know what’s going on with Taylor and Lady Gaga right?'" said Brittany.

Lady Gaga at the Grammy awards.

Taylor allegedly sent Brittany a "grovelling text message" saying how truly sorry he was and "what a great woman she is." They decided to "split their separate ways" after their incident, with Brittany calling him "disloyal and weak-willed".

At this stage, Brittany's claims are only allegations, but we can't help wondering if Lady Gaga knew about this part of Taylor's past.

CLICK THROUGH a gallery of the loved-up couple and THAT ring.

Lady Gaga and fiance Taylor Kinney

Lady Gaga's engagement ring

Lady Gaga and fiance Taylor Kinney

Lady Gaga and fiance Taylor Kinney

Lady Gaga with fiance Taylor Kinney

Lady Gaga with fiance Taylor Kinney

Lady Gaga's engagement ring

Lady Gaga shows off new engagement ring

Lady Gaga

Lady Gaga with her dog Asia

Lady Gaga shows off new hair

Lady Gaga

Lady Gaga with Stephen Oremus

Lady Gaga with CEO of the Academy Awards, Dawn Hudson

Lady Gaga at the Oscars

Lady Gaga at the Vanity Fair Oscars Party

Lady Gaga with Joan Collins

Lady Gaga

Lady Gaga shares a snap from the Grammy's red carpet.

Barely recognisable Lady Gaga shows her true colours

Lady Gaga gets a workout doing pilates

Lady Gaga's legs turn to goo goo after her workout.

Image via Instagram @ladygaga

Lady Gaga sees what all the fuss is about at the Oscars this week.

Lady Gaga does swimming pool yoga.

Lady Gaga shows us her pearly whites

Lady Gaga takes a break from song writing

Lady Gaga keeps things fresh.

Want more? Try:

Lady Gaga is engaged.

Is this Lady Gaga's most revealing outfit ever?

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