You should be checked to see if the anatomy of your nose is to blame. You might have a deviated septum. The septum sits between the sides of your nose and could be off center, thus blocking one side. This could be your problem, but it can be surgically corrected. Another possibility is polyps in the nose.
Polyps are just fleshy growths that can be removed, but they can block passages.
And yet another factor to consider is your teeth. Infections in your upper teeth can affect your sinuses. It does help how you feel, but the problem is that it sets you up for rebound headaches. They also claim nasal sprays may worsen the problem. At any rate their laser surgery creates scar tissue to prevent the turbinates from swelling so much and producing excess mucus.