Ok, so this freak accident happened with my BREEDER CORYDORAS when i was cleaning the tank. The water was murky with mulm and i was blindly rearranging decorations (stupid idea), in this case, my rocks. I grabbed what i thought was a rock cautiously and it turned out to be Ginger, my breeder peppered cory!
It started out as a mild hardly noticable scar, but now almost all of the left side of her head, except her eye, is covered in what looks like pink underskin, barely showing a slighlty open wound. I've been faithfully treating with melafix, or whatever that herby medicine is, and nothing has happened! She's heavily breathing and I dunno what do do anymore. Should i just "put her out of her misery"

I NEED HELP!!!