Oh my god! I feel sooo horrible! I was driving home from my boyfriend's house and I had no time to brake! A dog just darted out in front of my car while I was going 40 and I hit it. God...I feel so awful. It died. Ugh. I was freaking out. I was shaking and everything. I pulled over and called my boyfriend and started walking down the street. I saw him...then I saw 3 people standing around something on their driveway. It was the dog. Then woman walks up to me, I am sure she heard me crying, and asked if I was the one who hit it. Then she hugged me and tried to comfort me. I was freaking out. I was crying more than them. Ugh. I feel sooo horrible. I hate my new car! In my old car, I never hit a dog! In my new one, I have killed a frog and a dog. A dog is a little more serious than a frog, I know this. But I love frogs. I felt bad, but not as bad as I do now. God. I felt so horrible. 
It was so horrible. ugh. I was so shaken up. Man...I know that it must suck having your dog being hit by a car, but being the one who killed it. That's a different type of pain. I feel so guilty. I love animals so much. She said thank you for coming back. I couldn't just leave knowing it could still be in the road. God. How horrible for that to happen to your pet. Ugh. I am definitely taking something to help me sleep tonight.
It was so horrible. ugh. I was so shaken up. Man...I know that it must suck having your dog being hit by a car, but being the one who killed it. That's a different type of pain. I feel so guilty. I love animals so much. She said thank you for coming back. I couldn't just leave knowing it could still be in the road. God. How horrible for that to happen to your pet. Ugh. I am definitely taking something to help me sleep tonight.
It sounds like there was really nothing you could have done, but going back was a very kind and humane thing for you to do. A lot of people would have just kept going.
My drivers ed teacher, when I put on the brakes to keep from hitting a swooping mockingbird said in a very stiff tone "we never breat for small animals such as birds, squirrles, cats, and dogs." My thought was maybe YOU don't, but I sure as hell do.