I think people who suffer from health anxiety will tend to analyze any bad habits they may have. They will then zero in on possible diseases that can occur from those bad habits.
For example, you mentioned that you are an occasional drinker, and this could be the cause of the symptoms you are having. I bet they are just in your head because you are concentrating on your throat area. I just went through months of worrying about throat cancer because I too have been an occasional drinker. It's really the only vice I have. So, I naturally gravitated to one of the diseases you can get from drinking. My mind also had me thinking that I had some of the same symptoms as you.
It took two doctor visits to my regular doctor, and one to an ear/nose/throat doctor to finally make me feel better. This is going to sound odd coming from someone that suffers from health anxiety, but I am a very logical thinker. I simply could not be satisfied by a doctor telling me that nothing was there. I knew that my regular doctor could only see part way down my throat. So to tell me I was ok did not satisfy me. I wanted to know if there was something further down my throat. That's why I was really happy that the ear/nose/throat doctor sent the scope all the way down my throat for a look see. I needed hard evidence that nothing was down in my throat growing.
Maybe you to should have an ear/nose/throat doctor do the same procedure. I would think there is nothing better than actually going down there for a peek to actually see what's going on.
By the way, I told my regular doctor how much I drink. He said "Do you know how to tell when you drink too much?" I said "No....how?" He said "When you drink more than your doctor....and you don't drink more than me".
It was his way of telling me I am a light drinker. The ear/nose/throat doctor said since I don't smoke, and only drink occasionally, that my chances of ever getting throat cancer are very slim.
I hope this helps you!