I agree - you have 5-6 pounds, plus the fluid weight, along with the placenta weighing down on body parts not accustomed to that weight. While it could mean possible labour, you generally would also be having contractions regularly at the same time. More than likely it has no special meaning beyond normal pregnancy annoyances. You can ask your doctor and they can check to make sure nothing is wrong.
Baby is getting lower in pelvis.... it just gets worse girl but your getting close