It's the breeders responsibility to have the bile acid test done before selling the puppy. Take a stool sample in, and a urine sample if possible. You may have to walk behind the puppy with a big spoon and a small container and wait till it squats.
Make sure you have a small container to put it in. You can also pick up containers from the vet. (free) to put these samples in before your appointment. I'm sure the Vet. will let you know if he suspects a problem anywhere.