Rojales clinic

When i first went there there was a young doctor with a beard and he asked me in English if i needed any help when i looked if i was unsure what door to wait by so maybe I'll see if i can get him next time

I have been told by the receptionist at the Rojales clinic that i can only see the doctors named on the SIP card and that the sole English speaking gp there cannot accept any more patients as his allocation is full
Does anybody know how much an interpreter costs and how you go about arranging one to meet you there ?
Another question, if you are not happy with the care provided by your allocated doctor is there a process available to change doctors?