She is letting you know there is something wrong and definitely not normal and she is reacting to what she is feeling. Could she be in distress with labor? Something like bloat? Sounds like she is probably in a lot of pain and is obviously showing signs of extreme discomfort for some reason. Don't wait to see a vet, if that's something like bloat it is an extreme emergency. I hope she's okay and feeling better soon.
With respect I do get annoyed and upset that people ask other blurters on this site "what is wrong with my dog". There are enough signs in your dog to have her checked over by a vet. Please take her asap as this could be a medical problem. Please would you let me know what the vet. Says .Thank you.