yeah, +1 flower.
His swimming looks totally normal too me. Clowns are weird swimmers.
He may still be stressing, and honestly, that is okay. He went through alot and he is alone by himself. In my experience, fish do like other fish to be around, especially community fish because when something traumatic happens, and a fish finds itself alone, they think there is something wrong, like a predator or something.
It doesn't mean buy a fish... someday yes... now, no. but just a little piece of info that I have seen.
Also, once he does calm down a bit, what you can do, is move him the QT for about 3 weeks, (no less, maybe a little more) and treat him with copper. Then, if there are no other fish in the tank, the ich will completely die off, and as long as you QT everything, then you should be fine from there one out, with ich.
remember... ich can be on LR, corals, fish, even like snail shells and stuff, so whatever you can QT, that would be wise.
Also, freshwater dips help too. you can do this with your fishy, but wait til he isn't stressed out so much. maybe like 3 more days or so.
Good luck!