Bruno Mars is left with regrets and a broken heart on “When I Was Your Man,” the latest release from his sophomore album Unorthodox Jukebox, due December 11. Over a piano-driven melody, the R&B crooner sings about losing his girl to another man because he didn’t treat her right.

“I’ve never been this nervous. Can’t explain it,” tweeted Bruno before releasing the song to iTunes.

You can stream Unorthodox Jukebox in its entirety starting Tuesday at 12 p.m. EST on UnorthodoxJukebox.com.