Hi, dont worry, This has happened to me before. Ive noticed a loss of plug a couple of days before labour so if your bitch hangs on a couple more days it would make it about right for her.
Keep an eye out for anything else from the back end though, especially dark stuff as this would indicate a breakdown of the placentas. If you do notice anything else coming from her then run her down the vet so they can check if she's dialated.
Please let us know how she gets on.
Best wishes.

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