Anal pain is a symptom caused by "anal fissure" "hemorrhoids (piles)", and "anal abscess/anal fistula." However, anal pain may occur even if there are no hemorrhoids. There is also pain in which the pathological condition is not well understood.
"Functional anal pain" is a condition in which pain is felt in the anus without a clear cause like hemorrhoids. It is sometimes caused by excessive tension of the nerve or anal sphincter as a background, but pain sometimes occurs due to unknown cause.
Pain in the anus tends to be a symptom caused by hemorrhoids. Unlike hemorrhoid pain, pain occurs regardless of bowel movement.
It is regular folliculitis that develops on the skin around the anus. Folliculitis is a type of bacterial infection. Inflammation occurs to the hair follicles in the anus (where the hair roots are wrapped) and the pores become red. It occurs due to infection with bacteria when the anus is damaged or not clean.
Perianal folliculitis has very similar symptoms to anal fistula, which discharges pus and causes painful small lumps (swelling). It may cure spontaneously. If pain or swelling is severe, visit a hospital.