donna1964, there's two issues here, as I see it. Your delayed arrival and the dentist response. You don't say how much time you allowed for travel or delay, so being late is down to you, no ifs or buts. But I do sympathise, I will come back to that.
The fact that the receptionist couldn't have shown some understanding of your plight is probably why you have started this thread. She could easily explained, that which others have eloquently said, so sorry that you have had a wasted journey but we have to keep within guidelines and so on.........
Coming back to my first point, here's why I sympathise. My previous dentist had relieved me of not to considerable sum for fitting two crowns, a four figure sum in fact.
Some months later an abscess had formed under the work of one of those crowns and as always it happened at the weekend. Come Monday my cheek was protruding out with the swelling. I called at my dentist without an appointment, the receptionist could see my swollen face, she rang through to surgery, my dentist absolutely refused to see me without an appointment, adding that he could see me on Thursday.
Months later I started getting reminders that my dental check up was due, which I ignored. The reminders continued so I phoned the surgery. After explaining my previous plight the receptionist remembered me. I told her that I left the surgery in such pain that I went to my doctor, told the receptionist there of my frustration with my dentist. She spoke to my doctor after she had finished with her last patient. Doctor came out of surgery, looked the swelling in my mouth, agreed it was an abscess and prescribed antibiotics, it took about thirty seconds.
By the time that my dentist would have seen me the antibiotics were taking effect. With that I found another dentist and have been with that practice ever since. If you are paying privately it's your choice. Do you like the dentist that you are with? If so, write to the practice and tell them how you feel. How they reply will give you the understanding that you need to stay or change. I hope that helps.
Have any of you got all electric cars? Pros and cons please.