regret vs self-reproach

regret and self-reproach both are nouns.

Word	Noun	Adjective	Verb	Adverb
regret	Yes	No	Yes	No
self-reproach	Yes	No	No	No

As nouns, self-reproach is a hyponym of regret; that is, self-reproach is a word with a more specific, narrower meaning than regret:

Other hyponyms of regret include attrition, contriteness, contrition, compunction, remorse.

regret (noun)	self-reproach (noun)
sadness associated with some wrong done or some disappointment	the act of blaming yourself
	a feeling of deep regret (usually for some misdeed)

regret (verb)	self-reproach (verb)
decline formally or politely
express with regret
feel remorse for; feel sorry for; be contrite about
feel sad about the loss or absence of