'Tis the season for stuffy noses! Put a humidifier in her room and make sure it stays clean (no mold or dust!)!! Cool mist humidifiers are safest so they don't get burned by the steam, but you still need to be sure it is not pointed directly AT her. Near her is okay.
If you already have a warm air humidifier, go ahead and put it in the room to get moisture in the air. She is too young to be reaching up for it and pulling it over on her or holding her face or hand over the steam. Just be sure it is far enough away that it doesn't blow on her. IN the room is good enough. You can use the saline drops also. One or two drops, wait a little while, then gently use the sucker thingy.
I don't think she is allergic to your milk. Breast milk actually helps REDUCE the risk of allergies - and the longer you nurse the better for your baby! Best wishes to you and your little peanut!