Pregnancy possibility?

I recently had sex for the first time. I am 18 years old, and I've always had a fear of it, but I met someone who helped me through it. Well, I was talking it over with my mother and when I was conceived my father used the 'pull-out' method. And it obviously didn't work, I'm here. And with my younger brother she was on birth control for about 2 years. This information has made me uneasy. And I was curious what the chances would be of me becoming pregnant if I'm on birth control, we use protection, and he pulls out? We're talking all the precautions we can, neither of us are ready, or wanting to be parents any time soon. I would love for some feed back ASAP. Thank you.  

[miranty_fl]

When taken properly, birth control pills have the lowest pregnancy (failure) rate after sterilization. But "properly" here means a lot. You are advised to take the pill almost at the same time every day. The smaller the dose, the higher the failure rate when the schedule's altered. If there is changes in your metabolism like when you have disease or take medicine, the pill metabolism will be altered and may be not strong enough to prevent ovulation. At those conditions, you better have the pills with other protection (barrier contraception) until the next menstruation. Menstruation means you are not pregnant, so pills are safe to continue alone. Barrier here can be male condoms, female condoms, diaphragm, and cervical cap. Condom here has an advantage of STD prevention (but not for HPV).
"Pull out" method has the highest pregnancy (failure) rate.