Lady Gaga 'Broke Down a Few Times' While Recording 'Til It Happens to You,' Says Songwriter Diane Warren

"It was very emotional for her," Warren says of Lady Gaga's powerful recording session

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Lady Gaga‘s "Til It Happens to You" is an instant success – the emotional ballad became the sixth most popular song on iTunes in only one day – but recording the hit wasn’t as easy.

“It was very emotional for her,” legendary songwriter Diane Warren told PEOPLE at the National Women’s History Museum brunch in Los Angeles on Saturday. “She couldn’t even talk through it at times.”

The song was recorded for The Hunting Ground, a documentary about rape on college campuses, and hit close to home for Gaga. In December 2014, the singer revealed she was raped at the age of 19.

“I had heard she’d gone through this, so I knew she was the right artist,” said Warren, who was being honored at the event for her accomplishments. “She broke down a few times. She was very emotional doing the song. She put her whole heart and soul into it.”

All their work, passion and pain is paying off, as the song’s powerful music video has been seen more than 7 million times across the world.

“It’s taking on a life of its own,” Warren said. “I’ve never had something like this happen with one of my songs, though. It’s just the start for this. It’s such a powerful message. It’s obviously connecting.”

Although the tune brought up some troubling memories for Gaga, Warren insists they were able to work through the emotions while recording.

“It’s not like we were sitting around crying the whole time,” recalled Warren with a laugh. “We had fun too.”

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