He doesn't look happy. Is it RBTA? I have had them decide to walk and wander the tank for whatever reason, if they get under a rock they can deteriorate. If you can get him out which it looks like you did, you could try placing him in a small Tupperware with some rubble or small rocks and see if you can keep him from moving around and make sure he stays healthy and gets the light he needs. Anenomes can do funny things, one day look terrible and the next day look good as new, sometimes they will deflate. His foot looks healthy, which is good. Just try and keep him from moving around. Hopefully he doesnt look deflated with his mouth open as well, that might not turn out so good.
Good luck either way .