Dog Breeders - what do you think about this?

I purchased a female black / brown miniature Doberman from a breeder in Vereeniging. A week prior to this I had a telephonic discussion with her, she advised that she needs to keep the puppy there as it is under the infra-light and if I take her she afraid the puppy is small something might happen. Then she called again two days after saying I can pick the puppy up as the brother is taken & the mother is biting the pup, I agreed to pick the pup up that Saturday, she advised me to purchase a heating pad as well from her, she advised the puppy had her vaccinations. I had the puppy for less than a week, during this time the puppy was inactive & had blood droplets in her stoles, I assumed the inactivity was due to the fact that she was still small & it was cold. The blood in the stoles I wasn’t sure of as I didn’t know the symptoms of cat flu. Thursday the pup developed serious symptoms & it was only then that I knew something was seriously wrong. When we took her to the vet they diagnosed her with Parvovirus & said that this puppy was sick before I got her cau pups normally become infected with the virus & shows clinical signs usually become ill within 7-10 days of the initial infection. the pup died the same day. I called the breeder who advised that a refund or replacement is out of the question. I mean the dog was sick when I got her, surally a refund should apply. I have previously bought 2 pups from her before. She doesn’t care about the animals or customers cau if she did she would of handle this differently. What action should I take against her cau it is a lot of money for a sick dog, not only that the whole principal behind this, I mean if it had been a month I would of left it, but 5 days no its not on….