My 10 week old puppy has Parvo and he just pooped out blood and a worm...?

His original owner said the gave him his first set of shots and de-wormed him so we continued with his second vaccine. A couple weeks later he started showing symptoms of Parvo so we took him to the vet a couple days ago and he tested positive so we decided to do the at home treatment where we give him fluids in his back every 12 hours to keep him hydrated. He was doing pretty good and we saw improvement but today after we gave him his fluids he pooped blood and a worm came out. I looked online to see what kind of worm it was and from the pictures it looked like a round worm. I just don't know what to do or what the next step is. Please help me out. Its Sunday so everything is closed. =/