I am very new to fish keeping and aquariums, but I have a three gal tank with a beta fish and a nerite snail in it (plus a peace lily). A few days ago I noticed my snail on the ground with (what I think is) his trap door closed. I originally thought he was dead but he didn’t smell and I read that some nerites do this so I let him be. I immediately did a water change, and he started to move again. Two days later he was on the ground again, but a few hours later he is up and moving. His foot (is that what you call it?) looks really weird and I don’t think he is healthy but I don’t know what to do for him. Any suggestions would be welcome!