Whats the outcome of you letting your 5wk old liter of pups nurse too long?

The mother dog will wean them on her own (it is what they do in the wild). The pups may be eating puppy food, but may still nurse off the mom when she allows them. Allow the mom to nurse whenever she is willing. Keep the puppies with mom for a minimum of 8-10 weeks (10 being ideal). As mom starts feeding them less, you should begin offering more, and maybe allow the 2 smallest to eat out of a separate dish together.