Maybe you just need to visit [link|http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2002/12/08/TR199409.DTL|Chinatown]?
Seriously, a decongestant may be worth a try. Go through the [link|http://familydoctor.org/x2582.xml|flowchart]. There may be some pollen, etc., in the air that's flaring up and that you're allergic to and a decongestant may help.
HTH.
Hang in there!
Cheers,
Scott.
(Whose wife often has similar stuffiness symptoms after airplane trips.)