Yikes, I'm sorry. Birds are such delicate creatures. By the time they show symptoms of an ailment, the illness has most likely overwhelmed them. Is this veterinarian an ordinary vet? If s/he is, I would suggest you schedule an appointment with an avian veterinarian ASAP. Check the AAV's website for a list of local vets: http://aav.org/vet-lookup/

It's difficult to diagnose any animal on the Internet, but this is especially true with birds because the symptoms are so subtle.

Is she pooping okay? What about her appetite? If she's having diarrhea, it could signal something as mundane as missing bacteria in her stomach to something as fatal as kidney disease. In the meantime, the best you can do is follow the veterinarian's instructions and provide a warm, calm enviornment for Cloudy. With my ailing birds, I'll drape a towel over their cage and place a heat lamp about a foot away from the cage. I hope Cloudy gets better!