As of late, about every night for a week or two, it feels like my throat swells up. I do not think it is allergies because it happens at night and whenever I'm around pollen or dust it doesn't happen. Anyway, all day today it feels more swollen than before, and it's been happening all day. There is also excess mucus in my throat. What should I do? I took my allergy medicine (over the counter stuff) this morning, but it only helped for about an hour or two. What's wrong?