Cat about to die please help?

I was able to rescue a kitten off the side of the interstate the other night. Please don't judge me but I can't afford to take it to the vet. I love this cat very very much and have done everything I can. I had some leftover antibiotics from the vet when one of my cats had an upper respiratory about 2 months ago. I immediately put her on those and also have antibiotic eye meds because her eyes were messed up. (Apparently someone threw her out of a vehicle - all scabbed up from gravel and nearly starved to death). Well today she stopped eating and is too congested to breath through her nose. I know if cats can't smell their food they won't eat it. Any ideas? I tried one of those baby nose bulbs that you use to pull mucous out but not working. Maybe I'll up the dose on the antibiotic. I even put her in the bathroom with the hot shower running to help her breathe. Didn't work. Is it crazy to try Vick's or something like that???? Any ideas at all?? I really want to save this cat.