itching after bowel movement and trouble getting clean

I have had this problem for a little while now and wonder if it is hemmorhoids or something other. After I have a bowel movement, I clean myself as good as possible. Not matter how clean I get myself, I begin itching within an hour. If I let it go long enough, it is terrible! when I go back to clean myself again, there is more waste on the toilet paper, and sometimes if I let it go long enough, just a little blood. Very little.

If I am having this problem and defecate again, then it gets pretty painful.

I have no problems if I immediately shower after the bowel movement and clean the area thoroughly with soap and water. Is this Hemorhoids? fissures? Pinworms? what?