The dreaded parvovirus.....

A dog in our family was diagnosed with parvovirus, he was a toy fox terrier. He went 2 days without food and water before he was treated, we were all very naive to the virus. Little Tyco lost his battle after a 7 day fight. Now, a dog in my house has gotten it. He’s a 6 month old Chinese Pug, Goblin. My sister noticed Goblin was sick yesterday at 5 am and we had him treated by 8 am and brought him home. He vomited once, had diarrhea once, and didn’t eat or drink all day (he had a fluid injection under his skin) Last night out of nowhere Gobby got up and wanted to go outside, and he wanted to play he seemed back to normal , he seems okay today too. Now , we didn’t let him get all riled up because we want him to save his energy. Does this mean he’s going to pull through or could he still get worse?