gestation/whelping

Question
My 2 year old first gen shoodle (small size) is 61 days gestation today,she has been panting very heavily now for the best part of 3 weeks she has been bred back with a shih tzu of average size.she has been scratching around the whelping box and is very large and tight around her lower section(I am concerned the pups are to large) I can feel them and see the movement,she has no milk though her teats are much larger than normal.Should I be worried that she seems to be suffering and has not yet any milk..when should I reasonably take her to the vet she is off her food but is drinking small amounts of water,I have an appointment with the vet on Saturday when she will be 65 d/g is this to long to wait?
Thanks in advance for any information

Answer
I think I would go ahead and take her (if you haven't already resolved this) Many people don't realize that breeding a dog can include genetics five generations back in both male and female. You can have a larger schnauzer or poodle in the back ground of your dog and possibly have pups that are too large for her to have. Or you can have a breech or even an infection.
Hoping things are ok with both you and your girl
Cindi