As you suggest, your nasal symptoms are probably a response to allergies. The next step should be a trial of a prescription nasal steroid spray. Keep in mind that a nasal steroid spray does not provide immediate relief of symptoms. It may need to be used every day for several weeks to months for it to help. To get the most out of a nasal steroid spray use it after doing a nasal wash to remove mucus from the nose and sinuses.
If this fails to give complete relief, you should see an ENT specialist and ask if you might have a condition called atrophic rhinitis. Please read our allergic and non-allergic rhinitis information at http://www.nationaljewish.org/disease-info/diseases/allergy/about/conditions/rhinitis.aspx to learn more.