Allergies? Cold? What could help?
Vitamin D3 should do the trick. Usually during the winter the lack of sunlight (and hence vitamin D) weakens the immune system, rendering us more susceptible to allergies and colds: http://vitamind3blog.com/2011/01/vitamin-d-deficiency-linked-to-myriad-diseases/
Sounds familiar, and to repeat PPs I recommend a neti pot. I have pretty bad dust/pollen allergies and am trying to avoid drugs where possible. The idea of a neti pot freaked me out before, but I figured it was a worthwhile try at drug-free management of sinuses.
Boy does it work! After spending a week at my parents' dry and dusty house for the holidays, both DH and I got sinus colds. I used the pot as soon as we got home, and could see (and feel) the results immediately). Now I just have a bit of a dry cough which is resolving with lots of tea. DH is taking drugs and has been miserable.
They also sell plastic "neti pots" shaped like large bottles of saline nose drops. All you have to do is bend over the sink and squeeze the bottle and it works just like a net pot without having to tilt your head, etc. They are easier to wash, too. The only con is that they are plastic. But recyclable.