What Causes Gagging Sensation In Throat Along With Vomiting Up Of Sputum?

I am otherwise a reasonably healthy 85 year old female with a cough... a funny cough almost like a gagging episode I cannot stop, and it is night and day, and has bothered me of and on (mostly on) for about three years. It is like chronic bronchitis wit thick spithum sometimes and with thinner phelgm other times. I think it has to do with sinus which is terrible. Also, with old smoking habit of 40 years ago maybe. How can I get a good night s sleep? My throat seems to be the problems. A tickle starts there most of the time and I KNOW it s coming and must get some water quick to try to calm the spasm. Cough drops. Cough meds.