How would a doctor know if i need surgery for my deviated septum?

By examination: Usually a good examination is all that is needed. Because nasal obstruction can be caused by many factors, it is important to determine whether the septal deviation is the only cause of the patient's symptoms. If not, septal surgery alone may not correct the problem. You should see an ENT doctor or plastic surgeon with experience in treating these disorders.

Septal deviation: This can only be determined by physical examination. Be sure to have your nose evaluated by a board certified otolaryngologist.