Yeah the reason why is because the bigger u get the less room they have to move around. Completely normal. U should still feel the baby move at least 10x/hr they say but if u still feel movement then u should be fine
I got worried too my little boy didn't move that often towards the end it freaked me out to the point where I was gonna go in but I decided not too and he just came at 37w2d and he's perfect I think there's just no room for them
Yea sometimes she wants to be active sometimes she's just chilling I have to move my stomach to make sure she is ok and she'll move as if to say yes mom I'm good then go back to sleep lol