To be muddled or unable to act rationally due to success, excitement, or strong emotion; literally "to have one's head washed into confusion".

confused and dizzy; muddleheaded or scatterbrained; having a clouded or clouded mind

to feel one's head spinning or be so dizzy that one loses their sense of direction

to become dizzy with success or cloud one's judgment due to excitement or pride

to be in a muddle; to have a muddled head and be unable to think clearly