
I have to agree with all that 1-4 has written. I'd be alarmed if when the puppies shout to be fed, she won't respond but many's a time when my girls won't really want to be with their litters after say the first week or so, 24/7. I weighed mine once every day and for the most part, all gained. If the litter is ok with how much food they are getting, they will be quiet other than when actually feeding as some can get impatient as the teats are drained. If something isn't right, the litter will be noisy.
On another note, one of my girls who was a real 'prima donna' would pee her puppies, but when it came to the other - no way. Totally beneath her. As a result, despite my best efforts really, the poor dears spent much of their early days constipated! Gravity took care of a lot of it but I resorted to sitting them in warm water in the sink to help move things along. Obviously very shortly they were able to do this without help. She only had the one litter but she'd given me a super dog and bitch, so all was good.
I'd try not to interfere overly through the first 3 weeks. Your real work will begin once you start weaning them.