[I came home to new things today; I can't tell which eye has popeye o.o" now either it's gone away (very unlikely) or they're both swollen (probably). This is really getting out of hand.]
I looked again and he doesn't have both eyes swollen, thank god. But now he's got this weird, almost fuzzy, white growth, right before his anal fin. I tried to get a picture, but I was lucky I even noticed, and it doesn't help that the camera freaks him out. I'll edit the pictures post and replace some with better ones.
His eyes don't appear too swollen anymore. To be safe, continue treating him with Epsom for at least 10 days at 2tsp/gal. It is important to keep ahead of things like this since they can by symptoms of more serious problems. Continue with daily 100% water changes.
The lump in the dorsal is something that can't really by treated. It is either a tumor or lymphocytisis, it's hard to say. But either way it is something that you leave and just keep an eye on. I've had fish with these lumps in/on their fins before and they lived normal live spans.
Typically, since he appears to have a bacterial or fungal growth we would use Aquarium Salt but that would negate the Epsom Salt... It would be best to mix Epsom with a medication. You can try Jungle's Fungus Clear, it is really cheap (like $4 at Walmart) but still effective.
Thanks so much :D actually, I haven't started the epsom yet because it's hidden somewhere in the house. I've been keeping his water clean, so I guess that must be working. Also, it turns out that what I thought was a growth was just his silver belly swelling a bit... I'll just keep the water clean and start treatment asap. And I have to keep Comet's bowl clean, too, since he's been tail biting ever since I've been looking after his neighbor everyday >:C little pooper. I've just been a little frantic because it's the first time I've dealt with anything like this before ^___^; I hope I don't come off as over reactive or paranoid, heheh
Hah thanks :D it's actually been a pain since I have to siphon it twice a day instead of a normal change because the net doesn't fit in his bowl and he jumped out of my hand last time I tried to cup him, so he doesn't like my hand anymore. ugh. I need a heater and plastic canvas >:C
He's doing a bit better; I started him on the ES today. He's just being a little lethargic, but the swelling is going down. His colors are looking rusty, but that might just be because he's an old man. Comet's tail healed in and it was still clear before he chewed it again -____-" damn fish. Hopefully I'll have a heater for the tank before it gets really cold