Well, it sounds like it could possibly be allergies. Considering your situation, I'd agree with the previous respondent. Over the counter meds are going to be your best bet here.
I had bad pollen allergies till I got allergy shots for it. Before that, I used Claritin and that helped me to a certain degree. So I could recommend that one as well. Try a few (not at once) and you should hopefully find one that works for you. Be aware of the side effects of those meds too.
Hope you find relief soon!