Somebody left a puppy on my door step. I took puppy to vet and found out he was about 4 weeks. He hadn't gotten his balance to walk, just cutting teeth and still sucking or trying. I just lost my 15 yr old so this may have been a sign; However, I've never raised a puppy so young. I'm giving him puppy milk every 3 to 4 hours and soft canned food at least 3 times a day. When do I introduce dry puppy food. Potty training has been issue he will just pee where he stands, it doesn't matter how many times I put him on a pad. I've started walking him outside to potty train and that's not working.