Usually pancreatitis can only be diagnosed with a combination of clinical signs such as
vomiting, abdominal pain and fever along with a positive results for a specific blood test (probably the one your veterinarian had sent in), and confirmation with an abdominal ultrasound. In the meantime, you and your veterinarian should keep an open mind, and always ask the question, "What else can it be?", especially if your dog is not getting better.