Appointments aren't always available when you want!

Assuming that I’ll have an appointment just when you want it is incredibly annoying. Please don’t just call me up and tell me you want to come in today. I may not have an appointment. Definitely don’t be upset if I can’t get you in. It is not my problem that you waited until the last minute to call me. Don’t give me attitude if you can’t get want you want. Not my problem.