An 18-year-old has won the top prize at the American Music Awards.

Canadian Justin Bieber won artist of the year Sunday in Los Angeles at the 40th anniversary show, beating out Rihanna, Maroon 5, Drake, and Katy Perry.

The teenager said when he accepted his award that it was “hard growing up with everyone watching me” and he thanked his mother for “always believing in me.”

Bieber also won in the pop/rock album category for this album “Believe,” and he won the pop/rock male artist award.

Canadian Carly Rae Jepsen won favorite new artist.

New mom Adele from Britain took the top prize in the adult contemporary category.

Taylor Swift won her fifth consecutive award for favorite country female artist, while Luke Bryan won the country male prize.

Usher kicked off the three-hour televised show with green laser lights beaming onstage as he performed a medley of songs. Usher also took home the prize for best soul/R&B artist.

American Music Award nominees are selected based on sales and airplay, and fans chose the winners by voting online.