After anal sex why does your stomach feel like its runny or you pass gas is it 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 hurts the anus and rectum.