Could possibly be her mucus plug. Were you taking her temperature and did it drop at all (a good idea to begin when the colostrum comes in)? Behavioral signs can all be different since it is how they individually react to what is going on with their body so judging by nesting or anything like that may be useless if it's not something they are going to personally do, not all of them nest. Nesting, vomiting, shaking, squatting a lot, being clingy, not wanting you around, running in circles, being totally placid, looking surprised or confused (mini contractions we have no idea are happening), not wanting to eat, wanting to eat are all some of the more common behaviors but as you can see, some are complete opposites of each other and some dogs don't show any behavioral signs at all. Sounds like it may be very soon. You have a whelping box and your supplies and know what to expect and what signs mean there may be or is a problem? There is information and lots of helpful breeding and whelping links in the link below for you. Let me know how it goes please, Good Luck.
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