It's after Nina's song got sent to the star's management, who said they loved what she'd written.
"Apparently she (Rihanna) said it was beautiful and it gave me a confidence boost. It made me think, 'Maybe I'm alright at this after all.'"
Nina is now back with her first full album in three years.
In that time she's changed record label and has spent a lot of time "hiding away in a little cave in a little studio" like a "gremlin".
Since the release of her debut, Peroxide, in 2014, she's done a lot of writing for DJs and emerging artists - but the Rihanna interaction changed her perspective.
We don't know whether her song for Rihanna will pop up anytime soon, but the experience gave Nina a shake-up.
"When I write for myself I have barriers, but if I pretend I'm writing for a pop superstar then I don't have any boundaries."
Nina says she loves a "pop banger" and is one of the reasons she loves people like Taylor Swift.
"A song has to be about the artist's story. Say what you want about Taylor Swift but her songs are bangers and you can relate them to your life. They feel believable."
"With this album, I tried to write about subjects that were personal to me - but also have a poppy chorus and a big hook so people can sing-a-long."
The first song from her new album, The Moments I'm Missing, shows off that pop direction - which differs vastly from the more acoustic sound of Peroxide.
She says it shows her evolution as an artist.
"When I first started, Radio 1 was playing my songs before I even had an idea of who I was.
"That was amazing but I like so many types of music. It'll be cool for people to see the evolution on this new album.
"I love 90s R&B - TLC, Usher, Lauryn Hill. I've taken bits of that, bits of singer-songwriter and bits of pop and mashed them all together. I call it suburban pop."