PLEASE PLEAASE ANSWER i think my fish has dropsy?

my (common) goldfish has a red bump that i think is probably an ulcer on one side of his body, and on the other side his head is kind of sticking out a little bit. and near the red spot, it seems like his scales are starting to stick out, like dropsy, except the scales are really only sticking out a TINY bit, so i'm not sure if it is dropsy. my fish is acting mostly normal, except occasionally if i don't go near him for a while he goes to the bottom of the tank, but when i go near he's normal again. i put a tiny bit of fungus eliminator, but i was running out so it turned out i only put in about 1/4 or 1/2 of a teaspoon in there, and since it's a ten gallon tank it should have been two tps for it to work. so do you think he has dropsy and if so, would it hurt if i added maracyn plus even though i still added that litle bit of fungus eliminator? and the fungus eliminator was a different brand. thanks!!