We used this stuff called "baby noses" but it is basically just a saline solution for babies. There are a number of different brands. Drop a few drops in her nose, wait a few seconds and suction it all out with the bulb syringe. Baby might hate it, but my kids were happier after!
Also, you might slide a book or something under the crib/bassinet mattress to prop it so the baby sleeps on an incline.
and finally, my second baby had a constant cold thanks to the germy but loving older brother... We were given a nebulizer/inhaler when my daughter was so congested she was wheezy. It was hard for me to tell she was any different than just snotty with a cold, so it doesn't hurt to take a trip to the doctor if you have a sense that the baby is just miserable.
good luck. so sad when babies are ill!