Hello, I am 19 years old and still am unable to use a tampon. Whenever a guy fingers me it always causes me a lot of pain. I have never tried to have sex, but even if I did, I don t think the guy could get in there. I feel like there is something wrong, but I really don t want to go to the doctor if I don t have to since we don t have health insurance. I looked at the opening of my vagina and it is about the size of a pea or a little bigger.