What is the cause of twitching trembling or tingling in or around the anus?
If this happens in only the night it could be pinworms. They cant harm you in any way but you still would want to get rid of them. You get if you bite your nails (there would be eggs under them), or from sitting on dirty toilets. Try washing your bedding thuroughly. Sometimes the pinworms come out in your dung. Next time you have to go to the washroom look and see if there are any little white worms moveing. If they arent moveing than its just lint. This is contageous so make shure that you clean the toilet seats