I've always had upper back problems. But within the last week or so, I've noticed my tailbone feels like it's out of place and needs popped, especially after lying down. Even though I know that's probably not possible for tailbone to be out of whack lol. It's the weirdest thing. I'm only 10.5 weeks but I was wondering if this was a pregnancy thing or if others have felt their tailbones "out of place" too..?