A viral upper respiratory tract infection such as the one you have usually resolves within one to two weeks after infection. Symptoms can last longer, especially if you have concomitantly developed a viral bronchitis. This is an infection of the same virus in your lower airways in addition to your upper airways. The runny nose and sore throat resolve first, but the cough can go on for 3 weeks or even a month.
There are several advantages to going to see a doctor, even if you think you are getting better. First, seeing a doctor will help insure that your infection is not something more serious such as pneumonia. This would need treated with an antibiotic. You can also get prescriptions for medications that can help with your symptoms. You may benefit from a decongestant or cough reducer depending on which symptom is worse for you. These can help you get back on your feet. Finally, you can find out if what you have warrants keeping away from children or other vulnerable people that could get sicker from what you have. The best physician for you to see about this problem is your primary care physician
such as your family doctor
or internal medicine doctor