Mark
Dr. Borrowdale of Loyola did my surgery after biopsies done at another hospital showed SCC of the oral tongue.  If Dr. B said you're fine, believe him and try and relax a bit and put this out of your mind.  I would certainly keep a watch on things and go back for check-ups, but for now I would be assured that you DON'T have cancer.  I trust Dr. Borrowdale 100%, THE MAN SAVED MY LIFE.
You have taken a step in the right direction by quitting the smoking.  That alone may have caused the throat irritations, so you might be getting better because of it.
Wishing you well.