Justin Bieber swept the American Music Awards in Los Angeles Sunday night, and RadarOnline.com was backstage after the show, where Bieber fever infected everyone, including his fellow winners.

Watch the video on RadarOnline.com

Favorite Adult Contemporary Artist winner Michael Buble praised fellow Canadian Justin Bieber (even though the two haven't met yet), and had some playful words of warning in the press room.

• TAGS

• AMA
• American Media Awards
• Justin Bieber
• Michael Buble
• Usher