Joy--you sound just like me. I can turn a cough and a runny nose into HIV if you give me a minute.
There are lots, lots, lots of reasons for dry cough. The main ones that I would suggest to you are Post Nasal Drip, which is just drainage down the back of your throat, due to sinus issues. The drip makes your throat "tickle" and then you cough.
Also, you should consider Reflux. Most people who have symptoms of reflux don't even know they have them. When the acid splashes up into your esophagus, it causes irritation to your throat/windpipe. This irritation can cause coughing, which could be why it's worse when you lie down.
Your doc should do more than just put you on an antibiotic. Maybe you should visit an ENT (Ear, nose throat specialist). They can put a little camera/tube down your nose (totally painless) and actually see what's going on down there.
An ENT is definitely the way to go if I were you.
You said, "I did go to the Dr. and he but me on some anti-biotic...."
Did you return to the doctor when the antibiotic did nothing for the cough?
He needs to know this, so that he can decide what to do next.
Tell the doc about your concerns about heart disease and lung cancer.
Also, he can evaluate you for post nasal drip and for acid reflux.
(BTW, congrats on quitting smoking!)
If you haven't gone back to the doctor about this, he has no idea that what he prescribed didn't work.
You can get some baseline measurements to show him.
Take your temperature when you wake, and then sometime in the afternoon or evening.
Make a note of how much sleep you're getting for a couple days.
Are you feeling tired on 5-6 hours a night, or is it 8-9 hours?
Getting enough sleep is important for your immune system.
Cut out sodas and other sugars.
Eat fresh fruits and vegetables.
I don't know if you have an infection or not, but give your doc a chance to figure out what's wrong.
Hope you're feeling better soon.
My husband has had the same thing going on 3 months. He went to the doc. the first time, and they gave him and antibiotic and do guifensen with codiene but the cough continued. The next time I asked for a chest x-ray, and they said that he did not need one yet, so the gave him some steroid nasal spray and advair inhaler. That did not work, and now he still coughing. I have told him that he needs to call the doctor again, and demand a chest x-ray, or change doctors. He is still coughing very bad and it concerns me. His mother just pasted away from colon cancer, and I am concerned for him because his dad also past away from cancer. I hope that we can find some resolve soon or I will drve myself crazy.
My dry cough has some different symptoms. It occurs while speaking.
I have changed three doctors for the same issue since last one and half months. Even one ENT doctor done painting in my throat saying some infection is in my throat for dry cough but no relief finally visited new doctor and now I have some relief by taking steam and gargling with saline daily in the night and some medicines but not antibiotic and some cough syrup.