No it is not normal it indicateds the dog is eating way to much food so either 1. you are over feeding the puppy may or manynot be over weight but excessive amount of food can bass through the digestive tract of a puppy much faster with poor absorption leading to loose stools. or two, the quality of food is to low with and too much fiber. Too much fiber will cause loose stools as well. 3. Some food just don't work with individual dogs. There are many on here that swear by wellness. And looking at their dogs it works for them, Each and every time I have tried to feed it I end up with what you are experiencing now. I think a swich of dog food is in order.