I'm desperatly seeking help, my dog is very ill...?

a few days ago i noticed some bumps on his nose and they look very sore, so i asumed he got in a scufle with the neighbors cat so i've been puting perxoide on it and keeping it clean but just tonight he starting doing this aweful hacking/barking caugh and he seems very tired, not like normal, i took him out with my to the stable with me to visit relatives but on the car ride home he slept the whole way and i had to literally drag him out, he won't lift his head or open his eyes and his breathing is very shallow, to take him to the emercency vet clinic it could potentially be $800 so i want to see what anyone has to say before i do anything.. its very urgent