unthinkingly vs unthinking

unthinkingly is not an adjective while unthinking is an adjective.

Word	Noun	Adjective	Verb	Adverb
unthinkingly	No	No	No	Yes
unthinking	No	Yes	No	Yes

As adverbs, unthinkingly and unthinking are synonyms defined as:

Other synonyms of unthinkingly include thoughtlessly.

unthinkingly (adjective)	unthinking (adjective)
	without care or thought for others
	mentally sluggish
	not exhibiting or characterized by careful thought

unthinkingly (adverb)	unthinking (adverb)
in a thoughtless manner	in a thoughtless manner