I'm 15, want birthcontrol for fewer periods, what will happen at the first gyno appointment for this?

Okay so I'm 15 and a virgin. I had my first period on January 1st, 2009. Mine was really irregular and I hadn't had it in about 7 or 8 months but since about september 09 it has been normal. I am sooo self conscious over my period. I am constantly worried that I may have leaked or bled through. I hate getting up from my desk after a 45 minute cl just b/c there may be something on the seat or my pants. I'd be mortified. This happened before but luckily no one saw and i know how petrified i was then. I cant imagine how id be if the teacher and cl saw ( I was at lunch and waited til everyone was gone to leave and go to the nurse at that time). I always think people can tell I'm on it or they can see something. It's all in my head but it drives me crazy and worries me soooo much. If I didn't have as many periods I wouldn't always have to worry about it and it would make things easier. I have basically no cramps, a normal flow( not too heavy sometimes on the lighter side but normal all in all). My best friend has been on birth control since the day she turned 14. She uses seasonique and that's the one im interested in. When she went too the gyno for bc it was because of heavy flow and pain, they took blood test and asked questions then wrote the prescription and that was it. Will that be all they do to me? I'm scared to death of having a pap smear or pelvic exam. I realize i will one day have to have them done but if i don't have to just yet, id rather put up w/ the worry of a period than the worry of a pap smear/pelvic exam. What will happen if I go? Will it just be questions about my period, virginity,etc and blood work? Or should I expect something more?