Hi S.,
Sorry you're feeling crummy, when I got a bad cold and was nursing, I tried the Tylenol product, but it made me feel so bugged out I was afraid of what it was doing in my breastmilk. Call your advice nurse, or try taking a half dose and see if it works.
I do want to mention a couple of things with your daughter though. I recently ran across an article on dangers of using Vicks vapors under the nose to treat congestion, and even though it was under the nose that caused problems, I think it warrants caution, and you might want to think twice about using vapors at all. It has to do with artificially opening airways and the body compensating by creating more mucus. This is one article I found: http://news.yahoo.com/s/nm/20090113/hl_nm/us_vicks_children It's not the original one I read, in which the doctor said he would never use vapor products on anyone. And the ones I've seen are not to be used on babies under 6 months. Also, sorry to say, that unless the Little Noses is the saline spray, those baby decongestants were all pulled from the shelves last year, due to unsafe doses being administered incidentally to children.
For us, the saline spray kept my son's passages sufficiently lubricated when he was that little; that with the humidifier will probably be sufficient. Also, if you are breastfeeding, the instant a mother is exposed to germs, antibodies begin forming in the milk, and it is usually enough to fend of a serious cold for the baby.
Babies are born with about 300 unnatural chemicals in their bodies these days, and it's probably best to not add to that unless it's really a medical issue that can't be solved without it.....
Best wishes,
Colleen