Black Snakes are non-venomous. No poison. The only way its bite can harm you is if it gets infected. Wash the wound like you would any cut or scrape, put some bacterial ointment on it, and you're good to go.
I've been bitten numerous times... it's nothing. I kept lots of non-venomous snakes as pets in our carport in home built cages from the age of 7 until I left for college.
Watched them eat other critters I fed to them, watched them lay eggs, and watched the eggs hatch.
When I told my parents I was interested in doing this, they told me to get some books and memorize what the poisonous ones looked like, and the rest were okay.
Mom even caught a beautiful 6-foot Eastern Kingsnake for me one day while I was at school... she pinned its head down with a garden rake, grabbed it behind the head, and put it in one of my cages for me. She was cooler than cool.
