Clinic?

I'm going to the clinic to see about getting the depo shot and when I went to the clinic the other day, they said that since I'm under 18, I don't need an exam. Just a pregnancy test. But, when I called in to make an appointment, the lady said I needed an exam! So, what exactly do I need when I go to the clinic to get birth control? Do I need an exam? Do I just need a pregnancy test? I'm only 16 and I really don't want to go through an exam... it's kind of nerve-racking...