I have exposed skin on my anus it itches and causes sharp lingering pains, i have done research and it doesnt fit the description of any std/sti, what is happening to me?

?Prolapse?Hemorrhoid: Your anus might be squeezing some prolapse (pushed out) rectal wall lining. Another, and more painful could be prolapsed hemorroid. Thirdly cound be anal skin tag associated with anal fissure (Split in anal skin). You could try soothing rectal suppositories for immediate relief, but suggest you consult with proctologist to deal with the problem. Good Luck