My health

So since I have never been sexually active to this amount, I figured I should start going to a doctor more often to not only keep my gift healthy but also to prevent anything that could cause me to not get pregnant in the future. The thing is, I don't have insurance. I live at home, go to school full time, 18 credit hours = 6 classes, so I don't work. In the oldest of three and while both parents work, I take care of both brothers, who are 5 and 9. Although we have two incomes, we are still a low income family so we can't pay for insurance. The insurance in the family is from my fathers work and that's because he's had three heart attacks. So my question is, does anybody know where i can go to get checked up or for anything without it costing so much? I don't want to burden my parents with another financial issue. I'm trying for a job, hand on my heart, but with the very little time I have, I can't. And it's been my parents dream for a college graduate do I'm striving for that. Thank you ladies. I'm open to any suggestions.