Irritated with my mom

Ok so I started taking birth control in December. My gyno did a 6 month refill for me and told me that unless I had problems I didn't have to come back for another year. I called a few months ago when the 6 months was up to get my prescription refilled, which she did. I now have 3 more months until I'll need another refill, and my mom is bugging me to go to the gyno for an appointment. For what??? I still have three more months until I need a refill, and it hasn't even been a year since I've been there! She's also like, "don't go when you're on your period because they might want to do a pap." Why. I'm 18 and my doctor said last time I was there I don't need one until I'm 21. I've only been with one person and we both got tested so there's no reason to get a pap smear. I guess I'm just frustrated because I'm 18 and I'd like to decide what to do with my own body! What do you guys think?