Rectal damage can happen during trauma, medical procedures, or rough sex. Because the lining is thin and full of nerves, symptoms show up fast and are hard to ignore. Sharp pain is the headline. It feels like a knife or deep burn during and after the bowel movement, and can throb for hours. Bright-red bleeding is common. Blood drips into the bowl or shows on the paper, usually fresh and separate from the stool. Urgency and spasms follow. You feel a constant need to go, yet only a small amount comes out each time. Swelling and bruising appear. The anus... Learn more