Sir, I Have A Problem Sometimes When I Walk To

Sir, I have a problem sometimes when I walk to much and here are the symptoms. Walking and it hurts to walk to much sometimes I bleed or sweat from my rear then my underwear sticks to my rear and it hurts even worse or after the walk it hurts and it stops me from walking very fast or I have to take little steps to just get along. I am 62 years old and a male.