Whenever I call to make an appointment and my regu...

Whenever I call to make an appointment and my regular doctor isn't in, my wait time is always over two hours. I don't understand why!!!!!!!!!. When I get here the lobby is full. I then watch it go from full to empty, with the exception of me. Then it goes to full again as I watch every new person go to the back for their appointments. I cannot figure out, why not me, when is it my turn, remember I also have an appointment as well