
Pippa had 2 inverted nipples and 12 pups so I know exactly where you are coming from!
Ours are almost 2 weeks old now and the pups have sucked one of them out so it is pretty good, the other is still quite iffy.
We find she tends to wander off too though left to it she is being very responsible and they certainly aren't shouting or hungry. We have one very little one who tends to get pushed off by the bigger stronger ones...it is always going to be a problem with 12 mouths and only 6 good nipples! We tend to keep slotting her and as the others get tired she gets feeding. She isn't putting on weight as fast and is still small but I was advised on here not to supplement her.
We are going to start weaning them earlier than some might with it being such a big litter.
Hope this is helpful.