Finally going to a doctor

Hi everyone! I’ve struggled with anxiety and seasonal depression for awhile now. I had my first panic attack about 7 years ago when I was 15, and noticed symptoms of seasonal depression when I was 19. I’ve put off seeking treatment for these for the longest time, but I’ve finally made an appointment to see a doctor about getting on medication and the closer it gets, the more nervous I get about it. What should I expect?