The newly minted Grammy-winner tells EW about her hot new girl-power anthemand the funk influences of her next album.
The 22-year-old pop star debuted her new single, No, on Friday.
He said I have an album of Nice Meghan and that I needed to be sassy.

Credit: Dan MacMedan/WireImage
So I said, Im going to the studio to write you a smash!'
Trainor says it took little time to craft the song with hitmaker Ricky Reed.
We wrote it that day.
I was too scared to go by myself, she says.
So we had tequila, and then we played it.
L.A. played it 29 timesand we kept counting.
Ill never forget that moment.
On Trainors next album, she says shes broadening her pop sound.
People told me, Dont do what they expect,' she says.
Ive put some doo-wop on it.
It sounds like the girl version of a Bruno Mars record.
Its kind of a throwback.