Lady Doctor

I am 18, terrible periods and have never been to a lady doctor. I have had sex, I lost my virginity at 16. I am completely terrified to go to one. I made an appointment and will be there in December but I have no idea what to expect. My mom and I are not close, never was, and I have no girl friends to ask... basically.. what should I expect, also, I am going to get birth control aswell, but have no idea which to choose. I know all of them and what they do, I have studied them since freshman year in high school. How will I know which one is right for me? I wanted to be ttc with my boyfriend but we called that off once I told him I had ovarian cysts since I was 11 (had a drainage surgery because one cyst got the size of an orange). As we thought it would be too risky. I just keep rambling because I am very nervous to go and afraid to be judged..