Since last month I feel mucus or phlegm on back of my throat. Sometimes it feel like something is stuck in my throat. The feeling is worst at night. I consulted doctor when I started having this problem, I was prescribed Azithro and Amoxicillin, it didn't help. I was told that pharyngitis takes time to recover. I still have mucus, there is no cough, no fever, no other symptoms just mucus. Are there any diagnostic tests to find out what's wrong