I found a kitten??? help?

We were swimming when this kitten came out of the woods. We picked it up and it was skin and bones! so we took it home and we gave it food (we have a cat so we had cat food) and it bit me on an accident it was so hungry and i already doctored it and all but what do i need to do next? i got it to drink 5 ML of water out of a syringe because it wont drink out of a bowl. I really don't know what to do now cause the cat we had we got when he was 9 wks old and we actually knew how old he was but we do't know with this female and would we need to get her checked out by a vet? Oh and she has all her teeth so she eats hard food.