Dogs and pregnancy

Hi mommas! For those of you that have pups, when did they start noticing a difference in you, and how did they react?

I have two, my oldest is a 6year old lab mix male, and he’s always been my shadow. My youngest Luna, who is a terrier mix, definitely beats to her own drum. However, right around the 5 week mark Luna has been making sure she keeps an eye on me, and the both of them HAVE TO be laying near me (almost on me) whenever I’m in bed or on the couch. What are your experiences?

Also, (I know it’s a way away) but how did you introduce your babies to your pups, and how did they react?