Cara

Hi everyone. I am new to the fish thing, infact i did save my fish from certain death. and now i fear they are all on their way out anyway!! I have 3 goldfish and one comet. One of the goldfish has lost all its colour and is kinda lying on its side at the top of the tank. the other ones scales are all sticking out and seems to be bloating up and its head is sometimes down.... can anyone shed any light on this?? and what should i do.... i am a little bit panic stricken caus i hate to see any animals suffering...