I Have Been Suffering From The Flu For The Last

I have been suffering from the flu for the last three weeks with a few days where I was feeling like I had totally recovered. I am not feeling any normal flu symptoms and haven't had a chance to see my own doctor, but I have really bad pain in the middle of my back and on the left side and both hurt when I cough or sneeze. So I am wondering if I still have the flu or if it could something else?