B.J.
I worked at a Pediatrician's office for about 3 yrs. and each and every time there was a complaint of anal itching the doc ordered a test for pinworms. The test consists of a small bottle with a cap that had a sticky plastic stick attached to it. And the instructions were to place the sticky sided stick around the anal area after the child is sleeping because this is when the pinworms come out to "lay" the eggs. They will then get attached to the sticky stick and it will get sent to the lab. The symptoms you are describing sounds like a case of pinworms, and don't worry it's nothing uncommon! :)