dogs sensing pregnancy??

so little back story. my dog is the calmest most friendliest dog i’ve ever known, especially for how young she is (she’s 2). she literally will sleep all day if we let her, we take her outside to play and she will only play for a little bit and then wants to just hang out. we can be hanging out in our garage and people will walk by with other dogs and she just stays right by us, doesn’t go up to them, bark, growl or anything at anyone. she is always super friendly to everyone she meets. she never barks when people come to our house and the only time i had ever heard her growl was when she saw a bunny outside once lol. well now i’m almost 9 weeks pregnant and about 4 days before i found out (i waited till i was a week late from my period to take a test) we went about an hour out of town to go to the mall with some family (i live in a small town where we have to drive an hour to the closest mall😂😂) and anytime we leave for the day we put her in the garage with her food and water and she has access to the backyard to go out whenever she wants to. well on our way back we got a call from animal control that she had somehow got out of our yard and was chasing everyone that walked by our house and was growling and barking at them. i almost didn’t believe them because like i said in the year and a half we have had her she has NEVER acted that way towards anyone, not even strangers. until the next day when me and her were outside and i was putting something away in the garage and someone walked by and she ran up to them and was barking and growling at them, she stopped when i called her name to tell her to quit her shit lol (she’s never bit or hurt anyone). i was like wtf because she’s never ever done that before. fast forward a couple days i find out i’m pregnant and ever since then she growls and barks at every stranger that walks by our house, she’s barked at my boyfriend (her dad) that lives with us when he got home from work, and has just been very protective. i’m sure she knows i’m pregnant and i guess she knew before i even did, but i was just curious if anyone else has had anything like this happen with them and their dogs??? sorry for the long post too just wanted to share what i’ve been witnessing 😂😂