Sometimes kids are very still, and sometimes they are wild and crazy! This year, our young Boer doe was pregnant with 10lb twins, and we always felt movement. It was like putting your hand on a pillowcase with a monkey in it

At the same time, we had a Nubian doe that was due with 9lb twins, and I never felt a darn thing from them. Her triplet bucklings the year before were rascals and never stopped squirming.
Really, every doe with any kid is different. Takes a while for some to want to be squirrely, and that is probably the case for your doe.
Now, is she a first timer, or did she already have a loose udder before?