"3rd week - no voice and no Dr appointments available"

I am now into my 3rd week of not feeling well, and having no voice with a sore throat. I have already had to go private to get one course of antibiotics and am no better. I have tried to get two different appointments at my local surgery but am always advised to either call at 08: 00 or 13: 00 - but by the time I get through - the appointments have all gone. Since my surgery has opted for online appointment booking, for those of us who are not technically minded, it would appear getting an appointment with my Dr is now almost impossible.

The system and advice is always not to go to A&E etc. can anyone advise the next step please? Why should I have to go and see a Dr I don't know when I have a Dr who knows me and I have been seeing for 14 years already?