in great confusion vs heels over head

in great confusion and heels over head both are adverbs.

Word	Noun	Adjective	Verb	Adverb
in great confusion	No	No	No	Yes
heels over head	No	No	No	Yes

As adverbs, in great confusion and heels over head are synonyms defined as:

Other synonyms of in great confusion include head over heels, topsy-turvily, topsy-turvy.

in great confusion (adverb)	heels over head (adverb)
in disorderly haste	in disorderly haste