excessively vs too

excessively and too both are adverbs.

Word	Noun	Adjective	Verb	Adverb
excessively	No	No	No	Yes
too	No	No	No	Yes

As adverbs, excessively and too are synonyms defined as:

Other synonyms of excessively include overly, to a fault.

excessively (adverb)	too (adverb)
to a degree exceeding normal or proper limits	to a degree exceeding normal or proper limits
	in addition