The doctor has seen many girls your age, and some younger, so he'll know what to do for your first appointment.
Tell him what you've said to us here. If he/she agrees, he/she will perform the exams you're suggestion. If not, the doctor will explain why you don't need them.
Don't worry to much - just be honest about what you're experiencing physically, and what worries you. There is nothing you can tell the doc that they haven't heard already. :)
PS - good for you for going to the doctor! Most girls your age would avoid it so I'm glad you're being proactive.