★★★★☆
So, I went back to my favorite site and saw Ted's cold remedy. I didn't follow the whole thing, but I tried a hydrogen peroxide bath. The first time, I read it wrong and ended up putting the equivalent of a cup of 35% hp (about 12 cups of 3% hp). I immediately felt better--could breathe better, wasn't snotting everywhere, etc.
I wasn't totally better, but that was definitely the start of getting better. Went to work the next day, took a few more hp baths. This is definitely my new remedy I'll be researching and trying out!