sore throat

I had what appeared to be a bad sinus infection for a couple of weeks, thick green mucus from the nose and thick green plugs coming up in my throat.  All of that has dissappeared, and now I am left with a sore place in my throat on the right down low.  I also have a little coughing with this sometimes. I went to the doctor, and she said she thought it was viral.  That was on Friday.  It is now Tuesday and there has been no change.  It hurts to swallow, gets worse at night.  Did she diagnose this right and if so, how long should I expect it to last?