Try sugar. Eat some candy than relax to see if that gets her moving. She could just be running out of room at this point, could also try a heat pad or ice back to see if she reacts to that. If you haven't felt any movement, then call your doctor, they might just give you tips or have you come in to check on her.
usually at the 8th month the baby is growing alot more closer to the end oof the pregnancy and the baby has less room to grow but im not sure the babys cord could be wrapped aroung her/his neck i would deff talk to your ob about that...