word forming element indicating "oneself," also "automatic," from Old English use of self (pron.) in compounds, such as selfbana "suicide," selflice "self-love, pride, vanity, egotism," selfwill "free will." Middle English had self-witte "one's own knowledge and intelligence" (early 15c.).
OED counts 13 such compounds in Old English. Middle English Compendium lists four, counting the self-will group as a whole. It re-emerges as a living word-forming element mid-16c., "probably to a great extent by imitation or reminiscence of Greek compounds in (auto-)," and formed a great many words in the pamphlet disputes of the 17c.
1560s, "assail, trouble;" 1590s, "lay or impose as something that must be suffered," from Latin inflictus, past participle of infligere "to strike or dash against; inflict," from in- "in" (from PIE root *en "in") + fligere (past participle flictus) "to dash, strike" (see afflict). You inflict trouble on someone; you afflict someone with trouble. Shame on you.
<a href="https://www.etymonline.com/word/self-inflicted">Etymology of self-inflicted by etymonline</a>
Harper, D. (n.d.). Etymology of self-inflicted. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/self-inflicted