How Should Throat Infection, Cough, Back Pain With Tiredness Be Treated?

I am 57 years, Male and I am a scientific administrator.I was suffering from throat infection and cough. I was adviced Gembax for 5 days. My condition did not improve much. I ws put on Azithromycin 55mg for 3 days. Presently, I still have intermittent cough and low back pain and run down feeling. The sputum is not yellow or greenish yellow anymore. I am worried whether I have been given the right antibiotic as I am not fully fit. Please advice as I have to travel outside India shortly. Something for quick relief from pain, lethargic feeling , tierdness and the intermittent cough.