Justin Bieber's Top 6 AMA Moments

Justin Bieber Responds to Grammy Diss (ABC News)

Justin Bieber dominated the American Music Awards, scoring the coveted Artist of the Year trophy as well as the Favorite Pop/Male Artist and Favorite Pop/Rock Album awards.

But Bieber's night wasn't all wins: from his fashion to his on-stage match ups, some of the most memorable Bieber moments were downright bizarre. Read on for his highlights from last night:

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1. The harem pants. Only the Biebs would show up on a red carpet in harem pants, red studded loafers, and a shiny tank top, and shrug his shoulders like, "What?"

2. The Jenny McCarthy ambush. After presenting Bieber with the Pop/Rock Album of the Year award, the 40-year-old Playboy model buried her head in the 18-year-old singer's neck and kissed him vigorously. Bieber joked, "Wow, I feel violated right now." We're guessing Selena Gomez wasn't too pleased, either.

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3. The "haters" speech. Bieber dedicated his award for best pop/rock male artist to "all the haters," declaring, "I want to say this is for all the haters who thought I was just here for one or two years. I feel like I'm going to be here for a very long time."

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4. The mom. Mama Bieber, aka 38-year-old Pattie Mallette, accompanied her son on the red carpet. She got her moment in the spotlight when Bieber brought her on stage to accept the artist of the year award. "This is my mom," he said. "She's small but she's beautiful." He turned to her and added, "I want to thank you for everything. It's hard to grow up with everyone watching me. I want to tell you guys as long as you always believe in me I will always make you proud. Thank you and I love you."

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5. The acoustic rapping. Bieber performed a pared down rendition of his hit, "As Long As You Love Me," even rapping Big Sean's verse about a sometimes rocky relationship. He sings, he raps, he wears harem pants - what can't this guy do?

6. The Nicki Minaj collaboration. Bieber picked up the pace when he and Minaj came together for "Beauty and a Beat." Despite his recent breakup with Selena Gomez, Minaj's line about her, "I gotta keep my eye out for Selener," stayed in.

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