I found a turtle, how do I know if he's hurt?

Whats wrong with this turtle?

I live in the panhandle of florida. This turtle was in the middle of the road in front of my house for over an hour so I went to pick him up so he didnt get run over and he didnt even fight me when I picked him up. I brought him inside to find a spot on his belly, probably the size of a half dollar, rubbed completly raw. It looks like its from being drug around. Im sitting here now right next to him and hes breathing so loud it sounds like a dog panting. I was gonna let him go but I'm worried he's hurt. What should I do? Right now I have him laying on my dogs bed, I tried to feed him but he's not eating much. How do I give him water? He won't take any. I wish I could post a picture...

I would suggest to take him to a vet immediately

You should take him to the veterinary hospital as soon as possible.