sick cat with pneumonia???

has anyone else had a one year old cat with pneumonia? the vet didn't tell me anything encouraging, except that he "might survive because he's young" i just picked up Striker at the Humane Society a few weeks ago and is my first cat. I'm really worried, but is this nothing too serious since i now have him on anti biotics? i just feel so terrible that i didn't know what to do earlier. this is the greatest cat i've ever seen and would be devastated if i lost him. does anyone else have similiar experience(s)?

forlorn,
striker