I was hoping for a quick response to my request for more information as I have to get my dogs taken care of for the evening. I want you to have an answer though so I'll give you my thoughts now and when I get done, I'll come back and address any other questions you might have.
There are three stages to labor. During the first stage the cervix dilates and contractions begin. Your female will be uncomfortable, restless, pace and pant. This lasts 6-18 hours. I suspect that this might be the stage your female is in right now. During the second part of labor, your female's contractions begin in earnest. Her water breaks and puppies are delivered usually after 10-30 minutes of pushing. All puppies are born during this stage.
The third stage of labor is after all pups have been delivered and is when a dog still has small contractions to expell fluids and/or placentas from the uterus. You can read more about this here:
A dog’s gestational period (pregnancy) is approximately 63 days from breeding. One way of knowing when your dog with have her puppies is to take her temperature twice daily at the same time each day as her due date gets close. Keep a record of this. A dog’s normal temperature is between 101-102.5F degrees. Her temperature may rise and fall during this time, but once her temperature falls below 99 degrees, she should go into labor in the next 24 hours. The temperature drop is due to a reduction in serum progesterone levels and signals that the dog will start labor within 24 hours. You can read about this at:
You may also notice her breasts swelling during this last week of pregnancy and some milk leakage. Dogs will usually become restless and increase their digging and nesting behavior during the last week. You will notice an increase in her panting as well as a mucous discharge. You may also notice some abdominal contractions or rippling as her time grows closer. Do not be surprised if your dog is very restless and vomits as few times during this last week. Once your dog's temperature has dropped, please do not leave her alone in case of complications. As she enters actual labor you should be able to see her contractions and most dogs will begin looking at their hindquarters. An increase of licking of the genitals is normal before and during labor. Be sure and have an emergency Vet’s phone number readily available just in case of an emergency during the birthing of the puppies. Here is an excellent site about whelping.
Some other signs that my dogs always seem to exhibit are lack of appetite, frequent urination and frequent small, runny bowel movements in the day before labor starts which is frequently the first stage of labor. Frequently my dogs will start looking at their rears when the first real contractions start.
So if your girl has not had a loss of appetite, any vomiting of bile and frequent elimination then she might not even be in the first stage of labor especially if she is less than 63 days from her first breeding. If she does have any of those signs then she likely is in the first stage of labor especially if she is a smaller dog.
Let me also give you a site that discusses difficult labors and whelping. It will give you signs to look for indicating your girl needs to be seen by a vet.
Here is another article on dystocia.
When they indicate pushing, you can frequently see the stomach contract or pull up with contractions, so you might want to look for that . Females will often lick the vulva excessively when the second stage of labor starts as there can be leakage. Most dogs do yelp with the first pup. If you do not have experience whelping be sure to read the site I supplied.
I hope this information is helpful to you. If you would like any additional information or have more questions please don’t hesitate to press the reply to expert or continue conversation button so I can address any issues you still have . If you do find this helpful, please take this opportunity to rate my answer positively so I am compensated for my time. It will probably take me about an hour to get the dogs all settled, so I'll check back then.