Is growling normal when a dog starts to have contrations?

I am not positive of when my dog got pregnant because I went out of town twice once at the beginning of the month and the third week of the month and my cousin was dog sitting and she got out. I think she is due any day now, her teats are expressing milk and her belly is huge. This morning she started growling and barking every now and again for no reason. Is this normal, I have never had a dog that got pregnant.

Think back to how you felt when you started having contractions.Now, imagine that you had no idea what they were.You'd be cranky, too.

Aggression in a pregnant b*tch or one who recently whelped can be a sign of eclampsia. Eclampsia is due to reduced calcium in the bloodstream, and can actually be brought about by giving a pregnant b*tch calcium supplements during the pregnancy (in case you have been doing that). If this is what is going on, she will probably not be able to deliver her litter without medical treatment. If this is eclampsia, it is an acute emergency which needs to be seen now by your vet. Whatever is going on is not typical, and I would have this girl seen.