If caught and treated with support early (fluids, antibiotics, anti-nausea meds), many young puppies stand a good chance at survival and recovery.
Keep a real close eye on her for any changes and please get her back to your vet asap if her condition deteriorates.
You should be extremely concerned and cautious about her contact with other puppies and dogs. Parvovirus is extremely contagious and can be fatal. Thoroughly disinfect all areas/items she's been in contact with with Javel and/or Virkon (usually available at the vets). Do not let any dogs in areas she's eliminated in and prevent her, at all costs, from eliminating in public places that others, including humans, frequent. She will continue to be contagious to others for some time yet...ask your vet to be sure.
Glad she seems to be on the road to recovery