throat dryness and constant coughing

I have had a constant cough where white mucas will come up a small amount and am constantly clearing my throat. I will be talking and it will feel like a gag reflex to where I do gag like I am going to vomit. Also when I cough I gag real bad and I am not able to swallow saliva like my throat is constantly dry, I can swallow food and water ok but my saliva hardly goes down I have to force it down. Last night while sleeping I found myself unable to swallow at all and it scared me to where I slept sleeping up in a recliner because I was unable to breath right when I was trying to sleep and my throat was very very dry even after drinking water. I am worried what and why is this happening and what can I do. I have no health insurance.