Hello I need help, this is my first time having a fish for a pet, I have two bigger goldfishes and two small fishes that help clean the tank. I noticed a few days ago that one of my goldfish had redness around one of its eyes, and yesterday it turned fully black/bloodish and bigger than the other eye. I tried searching everywhere for what it could be but all I got was popeye disease and because it's just one fish and one eye that it could be an injury. An hour ago I wanted to isolate him, but while moving him he fell from my hand on the table, and there was blood left after him. I managed to put him back, but I am really worried since I still don't know what's wrong with him. He eats and swims normally and the only issue is the eye. If anyone could help in any way I will really appreciate it.