Sometimes when i try to poop my but hole hurts what could be the cause?

Before treatment...: Could you be referring to fissures, fistula, abscess? Sexually transmitted disease (syphilis, gc, hiv, etc.) should be considered. Hemorrhoids & rectal prolapse can appear as a painful swelling. Anal trauma of any kind may cause mechanical injury. Skin eruptions need to be considered. Examination required especially if symptoms persist, worsen, or are accompanied by bleeding.