So many of us are allergic to dust/mold and being indoors with our houses closed up concentrates all that. I highly recommend getting on your preferred antihistamine (they often take a few days to do their job) and using Sudafed (from behind the pharmacy counter) to get through the acute congestion for a day or two. My go to is Allegra/fexofenadine, Zyrtec is kind of weird-inducing for me.