Where can I receive a medical note to fly ? Any private doctors contact details.?

If you are being asked for this then surely it is because the carrier thinks you may be unfit or injured, in which case you will have been receiving treatment, so ask the doctors treating you for the certificate. Otherwise I fail to see why you are being asked for anything.

If you do need to go private there is the Policlinica Los Alcazares - the blue-fronted office across the road from Time4aChange. You will need to be able to get across what you want in Spanish, not necessarily with a doctor but certainly with the receptionists.