I'm sorry you're having difficulty hope. When you leave your appointment is that when they schedule your next appointment, if so doesn't the office staff give you a piece of paper with the appointment written down I know they always do that when I go to my psychiatrist if not why don't you ask them to write it down for you so you don't have to keep emailing or calling to confirm your appointments. You are right they shouldn't get upset with you for calling to reschedule or change your appointments but if you do it too often I can see where that can cause difficulty with the doctor trying to fill your slot. Is it possible to get a standing time each week so that you don't have to keep changing appointment times?