Nah, that ain't me - You say it when you're trying to look cool but you're actual

You say it when you're trying to look cool but you're actually just being stubborn.

Nah, that ain't me, I was just trying to be cool.

Nah, that ain't me, I didn't want to be the one who messed it up.

Nah, that ain't me, I was just being a pain in the ass.