It sounds like the whelping is going along well. What I'll do since it has been hours is give you some information in case a difficulty develops. The following sites go over dystocia (difficult or problems in whelping).
Here is another article on dystocia.
Here are some things you should look for after deliver to ensure she is remaining healthy. Bleeding after delivery is normal and it will gradually go from bright red to pale red, pink, tan until it disappears completely over the course of 3-5 weeks. If your dog has intense abdominal pain, pale gums and tongue, sudden drop in temperature or collapse she needs to be seen as soon as possible as she may have uterine torsion.
If your dog has a Green, smelly discharge from her vulva, fever, loss of appetite and listlessness, it is possible she has a uterine infection due to bacteria or a retained placenta and needs to be seen immediately. It is likely she has metritis which is a uterine infection.
If your dog is experiences muscle weakness, muscle spasms, tremors or seizures, limb paralyses, she needs to be seen now as it is possible she has eclampsia. Calcium supplements, Tums, cottage cheese or goat’s milk may help, but it might not reverse the symptoms quickly enough.
Here is a site with more information on this.
Look for breast infections on a regular basis. If a breast becomes inflamed, red and hard to the touch, your dog will need to be seen by your vet. Cut the puppies nails weekly to help prevent scratches to the breasts which might allow bacteria to enter the breast and lead to a breast infection.
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