A burning sensation in the anus or during and after a bowel movement is not an uncommon experience and every person may experience it at some point in time. Often it is related to eating spicy foods or during and after a bout of gastroenteritis. At other times burning is sign of proctitis, which in inflammation of the anus and rectum due to a host of causes. Skin diseases may also spread around the anus and in some cases, even into the anal canal...with out examination its hard to suggest consult nearest surgeon for second opinion they will do the needful.