Yay for you!
I had a similar experience with my Siamese. The breeder told us the kitten was older than it was so he could sell it earlier. We found this out by taking the kitten to the vet because it was doing so poorly. Consequently the kitten nearly died and we had to do round-the-clock care for a few days.
Be very proud of yourself for stepping up and giving life to your new puppy. His love for you will be endless and he will inspire you to stay sober.