My dog has been refusing to feed her 3 week old puppies. Do you have any advice?

Unfortunately our society does a very poor job of education people about the responsibilities of breeding dogs or even having them. Get some books and start doing the reading any responsible person would have done long ago. Successful Dog Breeding, by Chris Walkowicz, DMV would be a good one to start with.

I am sorry is this isn't the friendly, helpful answer you hoped for, but I find the misery resulting from poorly informed people breeding dogs, quite painful.