Lorde - Yellow Flicker Beat (Live at American... by uploaderdisney
She may not have actually been around to see it in it's original form -- but 18-year-old Lorde is one grunge rocker!

The New Zealander took to the stage at the 2014 American Music Awards on Sunday, and instead of being a somber moody gal -- she was all punk rock with her new single, "Yellow Flicker Beat" from soundtrack for The Hunger Games: Mockingjay - Part 1.

The teenager began the performance inside a box on the stage, then as the box lifted, the curly-haired songstress violently thrashed and head banged all around stage.

Lorde bounced around the stage in a white crop top and black pants as the star-studded audience watched. Lorde's BFF Taylor Swift, who opened the show with her new single "Blank Space," was in the crowd and couldn't help but dance around to the bumpin' tune. And judging fron the pics it looks like the feud between the baby goth and Taylor's longtime bestie Selena Gomez has ended.

Last January, Lorde said that Gomez’s hit song “Come & Get It” was antifeminist in an interview with Rolling Stone. “I’m a feminist and the theme of her song is, ‘When you’re ready, come and get it from me. ... I’m sick of women being portrayed this way.”

Gomez did her best to combat the Grammy winner's words with her Flaunt magazine, saying, “That’s not feminism. [Lorde is] not supporting other women. That’s my honest opinion, that’s what I would say to her if I saw her.”

Well it looks like that troubled water's all under the bridge now! Taylor Swift really can fix anything -- even girl fights!

After the AMAs, we bet all three of them baked some cookies and braided each other's hair -- aka T-Swift's dream night.