We think that she needs to be seen by a veterinarian immediately. You mention that she made the nest from pine needles which is of concern. Not only can the needles and their sap be extremely harmful to young birds' feathers, but a needle that is stuck in the mouth or other parts of the body can cause a nasty, and sometimes fatal abscess. She may have been poked by one of the needles while sitting on the nest and an abscess formed. If this is the case, the wound needs to be lanced and antibiotics prescribed quickly.

If you cannot find a wildlife hospital to look at her, try to find an avian/waterfowl exotic wildlife veterinarian in your area. If you have a university with a veterinary medical school, they may see and treat her as a learning tool for their veterinary students. Please let us know how this progresses. The Regal Swan