Caring for a Puppy with Parvo?

I adopted a Catahoula Leopard dog from the shelter on 3/20/2017. I was told she is almost 3 months old. She seemed very shy and timid when we adopted her and brought her home. She began vomiting and I thought it was because she was nervous or had car sickness. The next day when I got home from work, I took her outside and she had bloody diarrhea. I called the shelter immediately and they told me to bring her in. When I call they say there is no improvement. Should I be taking her to an animal hospital or caring for her at home? I worry that they do not have 24 hour monitoring or enough staff to help my baby get better.