What\'s wrong with my Goldfish?

Just any ordinary day I discovered my goldfish overturned, stuck between a plant and the edge of the tank. I was alarmed at first, believing that my goldfish had died but it was able to squeeze out. Now for some reason, its fins seem covered with blood it cannot swim with one fin. It is obviously struggling. I usually check o my fish and it was perfectly fine, no blood or broken fins. The plant and edge of wall weren't too small, not enough to get a fin broken at least. My goldfish also seems bloated abit. I don't feed it too much but it seems much rounder than usual. The other fish like nibbling at it, even after I had fed them so I don't think the problem is overeating. What should I do?

size of the tank?
how many other fish do you have an what kind are they?
how long have you had the tank up and running?
how often do you do water changes and ow much water do you change?

a little more info is needed.

Separate the fish and get them different tanks

Redness that looks like blood streaks in the fins and on the body is a fish disease known as bacterial hemorrhagic septicemia, which is caused by bacteria such as psuedomomas, aeromonas and streptoccus. This disease doesn't however cause bloating of a fish, this is otherwise known as dropsy, which unfortunately is fatal to fish. Dropsy is though caused by one of the same bacteria, aeromonas, so the septicemia could be a secondary bacterial infection to the dropsy. Dropsy causes fish to appear bloated due to fluid building up in the fish's body cavity. It can also cause the fish's scales to stick out from the body and also in advanced cases for the fish to float upside down. Both of these conditions can be treated with API's Melafix, although if the dropsy is caused by internal parasites then unfortunately treatment wasn't result in curing your fish. I'd try and seperate the fish to decrease the chances of the other fish catching a disease. Remember to remove the activated carbon from your filter otherwise any medications you use will be filtered out of the water before the can be effectively used to treat your fish. Good luck!