A perineal hernia may or may not cause a visible bulging or swelling under the skin. If there is a bulge it may be quite large. Sitting can be uncomfortable or difficult. Pain in the rectum, fever, swelling on one side of the buttock, difficulty urinating, and general malaise are other symptoms of perineal hernia. If a bulge is visible the hernia may be misdiagnosed as an inguinal or femoral hernia.