I found it! It was actually called "The Wrong Way To Use Healing Magic". I believe in 2021 it got approved for an anime, but the manga is pretty hilarious. The main character basically got summoned on accident, and learned he had an affinity for healing magic, to which he begins some rather nightmarish training, because he can just heal his body if it becomes injured. It isn't a super amazing read, but it is rather enjoyable.

I dunno. There's a few animes that did similar. I'd have to find it, but there was one that was called something like "battle healer" who, at one point, started throwing punches infused with healing energy, just so he could beat them up some more, lol