I personally believe this song is about him and his girlfriend breaking up, and by the way he puts it, he's trying to be rebellious by going out and doing everything he always wanted to do with no repercussions. Who says he can't call up someone he used to know? Who says he can't party in New York city? He still feels a lot of sadness because when the party ends, it's still him by himself, and you can tell that by the contrast in the music video; the bright lights when he's out with friends, to the darker colors when he's alone.
I personally believe this song is about him and his girlfriend breaking up, and by the way he puts it, he's trying to be rebellious by going out and doing everything he always wanted to do with no repercussions. Who says he can't call up someone he used to know? Who says he can't party in New York city? He still feels a lot of sadness because when the party ends, it's still him by himself, and you can tell that by the contrast in the music video; the bright lights when he's out with friends, to the darker colors when he's alone.