I am so very sorry to hear that Copper is ill
I can only imagine how you must be feeling. I know how deeply we love our little furbabies. Just remember that Copper is young and clearly has been very well loved and cared for and because of you being such a good mom to him he has the very best chance of recovering quickly. I know that it is hard to think positive when faced with the illness of one you love so much but you took charge of the situation very quickly and I am sure he is getting great medical care.
Know that I am sending prayers for his speedy recovery. Take care of yourself, try and get some sleep and please let us know if you hear anything from the vet.