Hi Crazyelk:
So sorry to hear your baby is sick. I can so relate to this, I've been dealing with similar things in my 7 week olds for the last 3 weeks.
Isolate her from any others. Extra TLC will help anyone.
Grind up her chick feed very fine and mix it with a little plain yogurt, then water this down so that it will easily go through a medicine dropper. Place one drop at a time on the top of her beak and let her swallow it or shake it off.
Do not place any liquid or slurry food into an open beak!! This can be deadly.
The yogurt will help her digestive tract to develop good bacteria to fight infection. You can also get her to take 2 drops of baby vitamins (no iron added, please) on her beak - this can help her get the nutrition she needs if she is not eating because she doesn't feel well.
Absolutely essential to help her to drink and eat a slurry of above. If she won't eat the chick feed slurry then try mixing a little water and babyfood oatmeal and applesauce mixture and drop that onto her beak. It comes in a little jar and you will only need to mix up a very small amount at a time. Same for the chick food / yogurt / water mix above.
If she doesn't eat or drink she will go down hill very quickly. Keep watching the eyes, nose, and listen to her breathe.
Your case maybe different than mine but my first sick ones didn't really have the clear respiratory symptoms, just the closed or swollen eye and off their feed, water, and just sitting around.
Later I realized once others got sick and had the respiratory symptoms that I needed to give them an antibiotic. I used LS-50 mixed into the water. It took mine about 5 days to really start to improve but then I was messing around for a week or so trying to figure out what they had. I did loose 4 of my birds, still have 3 that are about 80% and the rest appear to be just fine.
The gatorade mixed into the feed or oatmeal babyfood would probably work too.
I did have to flavor the medicated water to get them to drink it. I use a little sugar. Oh, you must mix the antibiotic water fresh each day,it become ineffective if you don't. Just good to know.
I also dripped sterile saline water on the closed eye to keep it clean and moist. Mine seemed to scratch at it. Also a product called VetRx is good to help with breathing in the nostrils if they get crusty.
Hopefully, some others with more experience than me will jump in here and offer suggestions for you. I just thought that I would offer what I can until then.
Hope she recovers soon,
Posey