Goldfish are very messy fish. They create a lot of ammonia, and orandas reach an adult size of 6-7 inches (just google it.) One goldfish needs at least 20 gallons and then 10 additional gallons for each extra goldfish.
Point is, your tank is too small. At this point, you should be doing 25% water changes every day to keep the ammonia levels down. Don't be mislead into thinking that they will not grow that big because you keep them in a small tank. Lots of problems can occur if you don't provide them with enough room.
I'd suggest either replacing the fish (returning them to the store, DO NOT release them into the wild. In most states that is illegal and can cause huge problems.) with a betta or some shrimp or get a larger tank (craigslist has lots of cheap tanks.) You will also need a filter. If you don't have a filter, you shouldn't have fish. It is vital to their health.
I'd recommend joining an aquatic-related forum as well to get quality information from experienced people who know what they're talking about.