Sounds like pinworm infection, go see a doctor.
Also, its contagious because of the eggs so people you were around may get it too.
The female worms lay up to 10,000 eggs at a time.
If you don't see a doctor they may not go away, and it can get worse if you don't as it can lead to a worse infection. And that infection could possibly lead to death, assuming you get a real bad one of course.