experience vs happening

experience and happening both are nouns.

Word	Noun	Adjective	Verb	Adverb
experience	Yes	No	Yes	No
happening	Yes	No	No	No

As nouns, happening is a hypernym of experience; that is, happening is a word with a broader meaning than experience:

Other hypernyms of experience include natural event, occurrence, occurrent.

experience (noun)	happening (noun)
the content of direct observation or participation in an event	an event that happens
the accumulation of knowledge or skill that results from direct participation in events or activities
an event as apprehended

experience (verb)	happening (verb)
undergo
have firsthand knowledge of states, situations, emotions, or sensations
undergo an emotional sensation or be in a particular state of mind
go through (mental or physical states or experiences)
undergo or live through a difficult experience