My head's under water,
But I'm breathing fine.
You're crazy and I'm out of my mind
...out of one's mind/head
(fig.) - to be silly and senseless; to be crazy and irrational. (Typically: be ~; go ~.)
Why did you do that? You must be out of your mind
Don't drive so fast, Tom! You have to be out of your head
! (McGraw-Hill Dictionary of American Idioms and Phrasal Verbs)
"The world was a fantastic, marvelous, awesome place, Rose decided."