You are most likely having Deviated Nasal Septum
, but in addition to that you may be having Allergic Rhinitis
. First of all you should get treatment for this allergy,for example tablets of Levocetrizine or Fexofenadine
and Steroid nasal spray. Many cases of Deviated nasal septum without any history of nasal obstruction
or headache don't require surgery. If there is persistent nasal obstruction or headache even after treatment by medicines & nasal sprays then you may require surgery.