My ferret is bleeding?

I just got a young ferret from a couple last night and it was obviously malnourished and they didn't bathe it as much as they should've. I just gave him his first bath here- or at least I tried to- and his skin was reddish. Eventually the water was "reddish" as well. He was bleeding from flea bite wounds. I bathed him with a small dime sized amount of doggy shampoo. Would that make it burn? ( I know you're supposed to use kitty shampoo but I didn't have any!!!!) What can I do to make the wounds heal?