Goldfish Pregnant?

Question
Hi, I have a 10 gallon tank with two fish in it. I used to have another one that was very old (about 8 yrs.) but it died a couple months ago. The other two Yukon and Angel are younger, Yukon is quite small and only about two years old, while Angel is older (about 6) and I think she is a veiltail,and medium/large. I do not know what sex they are.
    
   We have been on vacation for a week and when we got back Angel was very round and quite anxious. The water was also kind of cloudy, but we didn't clean the tank yet, because I heard if she was pregnant we shouldn't clean the tank. I don't know if she is though, because she is very old and we don't know if Yukon is a boy or girl. Do you think she is pregnant and if she is what should I do?

Answer
It is more likely she has swim bladder disease.

Do water changes twice weekly, add about a tablespoon of aquarium salt, and feed shelled peas for a bit. It may go away.

Oh, and 10 gallons is not suitable in any way for even a single goldfish, so chances are the disease will just come back. But you can put it off for a bit.

-Nick