a wild hair up my butt
You’re so clueless you think your butt can think for you and it’s not working.
I drove the wrong way on the highway. A wild hair up my butt, and I didn’t even notice.
I told my boss I was sick, then went to the movies. A wild hair up my butt, I’m not even sorry.
I tried to cook and set the fire alarm off. A wild hair up my butt, that’s what I got.