"Rude manner"

Having skin issues myself I have always had good experiences with dermatology but the phone conversation I just had trying to rearrange an appointment for my daughter was borderline rude and unprofessional. Her first appointment was made during her GCSE exams so we called and it was rearranged for just before. This has been cancelled and rearranged for again during her Exams so I called yesterday to rearrange. I was told the person was on a call and would call back. I never received a call however they said they left a voicemail ( I do not have an answer machine service so I'm unsure where this was left). I called again today to politely explain that she couldn't do the date they set due to it being in Exam month. I was told HE had checked himself and he had rearranged it for a couple of days after exams finished as there are no exams. I checked the diary and there is still important things happening in school that day that she cannot miss so I said she couldn't do that date. I was met with a rude "why can't you do that date?" not that I should have to explain but I did. I was then huffed at and told he would have to search as we have cancelled quite a few appointments. I said we had not and that the hospital keeps cancelling to have him point out that I cancelled the first one..which I did not-i rearranged the date they sent out as she couldn't do it. He then continued to point out that meant I have cancelled things my end too. I realised I was dealing with a rude person and waited for him to just give me a new appointment date. He came back with September ( annoying she has to wait so long after their cancellation but understandable.). He also seemed to be quite smug that we would wait now and that we would go to a different hospital. I have no issue with the appointment being cancelled by them and no issue waiting for a new one-my issue is the rudeness of the doctor?nurse I spoke to. Couldn't tell you who it was or what his job is as he didn't bother to tell me