It is possible to feel like you have them even when you don't actually have them, especially if you are feeling it during the day rather than at night. I had this, and it turns out that I was washing my bottom too thoroughly and making the skin there super sensitive - I've explained more about it here if you want to read: https://patient.info/forums/discuss/signs-you-might-not-have-threadworms-451959
If you have definitely seen threadworms then that is another matter. Either way, I think the best option is to talk to your parents, and go to see a doctor.