All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad (saw) is His slave and Messenger. Whether or not you are certain that you harmed this dog, you are not required to do anything. You do not have to give charity or expiation as you are not sinful for what happened, because the one who does something by mistake is excused and is not held responsible for his act, as Allah Says (what means): {And there is no blame upon you for that in which you have erred but [only for] what your hearts intended.} [Quran 33:5] Allah knows best. (Source: islam_web) Classified in Foods, Drinks, Clothes and Adornment > Hunting