I Had This Dry Cough That Wont Go Away For

I had this dry cough that wont go away for more than a month, at times my throat feels so hard and heavy like I am about to burp, no hiccups or burping. By the cough continues especially while sleeping, I have tried all sorts of off the counter coughing meds for dry cough. Nothing helps, how can I get rid of this cough and heavy feeling in my throat?