Perhaps its just the way You worded it, If Your at the 6 week stage and add 4, I will let You do the maths From the picture the bitch does not look in pup, but for the sake of a few quid I would get Her scanned for My own piece of mind, could be one or two tucked away in Her rib cage.
I have always found the nipples a good indication that things are looking good at about the 21 to 28 day stage. I always had My bitche`s scanned at 35 days just so I can plan in advance.
Thorny
Cheers pal think its worth a do just for peice of mind, she is 8 year old to and never hed a litter before thats