Meghan Trainor Sounds Off on New Boyfriend Rumors and J.Lo's Dating Advice

'A boyfriend sounds great!' the 21-year-old gushed.

Fresh off a banner year, Meghan Trainor's 2015 is already off to a great start.

"Lips Are Movin'," Trainor's follow-up single to her massive hit "All About That Bass," has already been certified platinum, and the singer rang in the New Year just one week after celebrating her 21st birthday.

"I was on the Jingle Ball tour, the whole arena sang ['Happy Birthday'] to me," Trainor tells Entertainment Tonight's Nischelle Turner, describing the moment as "epic!"

NEWS: Is This Meghan Trainor's New Boyfriend?

Pal Nick Jonas helped Trainor celebrate her big day, while speculation began to swirl over whether Jonas had also played matchmaker. His assistant Cory Anderson shared a sweet photo of Trainor on Instagram, kissing her on the cheek. The moment was captioned: "Every inch of you is perfect from the bottom to the top," referencing Trainor's own lyrics.

"He's a good friend," Trainor tells ET of Anderson, but stops shy of calling him her boyfriend. "He's great, he's cool," she says, carefully adding: "I'd love to have a boyfriend. A boyfriend sounds great! I didn't realize the whole world wanted to know about it, so I didn’t know how to deal with that but I'll learn."

WATCH: Inside Meghan Trainor's Rapid Rise to Stardom

And who knows more about high-profile romances than Jennifer Lopez? While insiders say that the 45-year-old superstar is back on with former flame Casper Smart, she also offered some words of wisdom to Trainor at the American Music Awards back in November.

"I was star struck the whole time," Trainor says. "I told her Selena the movie was the reason I wanted to become a singer, and then I asked her a bunch of questions like how do you have boyfriends in this industry?"

Lopez's response: "Be very picky."

Trainor's interview airs Wednesday on Entertainment Tonight, while J.Lo also returns to the small screen for American Idol's season 14 premiere.

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