Toddler might have pinworms 😩

She itches mainly at night. She itches both vagina and anus. She has had a stomach ache. She fights to go to sleep. I didn’t put these three together until I was looking up what could be giving her stomach aches. I had the doctor check about the stomach ache, last week and the doctor said to give her miralax for a month because she was constipated last month. I am going to get another appointment for her to check for pinworms. Any advice? Anyone deal with this with their kids? Im really worried, I didn’t know this was a thing.