So i had anal sex the other day but after a hour since we were done it started to burn and i had diarrhea it laste 48hr. is that normal?

Doctor can examine: Anuses are not designed for in-out, in-out sex. Just like in a big city, some streets are one-way and some streets are two-way. A vagina is created or evolved to be a two-way street (penis in and out, baby out). The gastrointestinal tract is designed to be one-way, with an opening on each end. Food goes in the mouth, and the brown stuff goes out the butt. Friction, trauma damages anus and rectum.