After a brief hiatus from the spotlight, Demi Lovato is back with brand new music all her own, and she?s not sorry. The 24-year-old pop princess dropped her new single, ?Sorry Not Sorry,? at midnight on Tuesday, and the badass anthem is sure to have you dancing your Tuesday blues away. ?Now I?m out here looking like revenge, feeling like a 10, the best I ever been. And yeah, I know, how bad it must hurt to see me like this, but it gets worse,? she teases in the opening lyric.