If your belly button piercing appears to be infected, the signs may include redness, pain, heat, swelling, or pus discharge. You can get an infection if you fail to clean your piercing well or you touch it with dirty hands. To assist this, gently clean it with saline solution and avoid using harsh products on the area. Also, do not remove any jewelry from inside the piercing until advised otherwise by a professional. Visit a dermatologist if there is no improvement.