"Disclosing your medical problems with a receptionist"

Recently when calling for a gp appointment I am asked by the receptionist what I want to see the doctor for.  When I advised that I felt I should only be discussing this with the gp I was told that is fine but they would have to tell the doctor I have refused to tell them, and advised that the reason for this is to direct my appointment to the most appropriate doctor. I felt quite intimidated and very uncomfortable by this so eventually explained why I wanted to see gp. 

I feel it is extremely inappropriate to feel pressurised into disclosing your medical problems with a receptionist and feel this isn't a valid reason for doing so as it is near impossible to secure an appointment with any doctor never mind a specific one for a specific ailment (I have to call every morning and usually over 100 times before I get through and am then normally told there are no appointments left and to call back the next day)  so I really don't understand their reasons for this. I also feel it is breaching patient confidentiality to disclose your medical problems with a receptionist as I thought your medical/health,  concerns/ailments were only shared on a need to know basis with other medical professionals