Old vs early

Old and early both are adjectives.

Word	Noun	Adjective	Verb	Adverb
Old	No	Yes	No	No
early	No	Yes	No	Yes

Old (adjective)	early (adjective)
of a very early stage in development	at or near the beginning of a period of time or course of events or before the usual or expected time
	of an early stage in the development of a language or literature
	being or occurring at an early stage of development
	belonging to the distant past
	very young
	expected in the near future

Old (adverb)	early (adverb)
	before the usual time or the time expected
	during an early stage
	in good time