When guinea pigs are hard inside the womb and are not moving much; what does it mean?

My guinea pig has been pregnant for 69 days now, and her babies are barely moving. There are hard spots in her belly (harder than what they felt about a week ago) and soft spots that weren't there a week ago. Now her belly has hard spots which are the babies and soft spots that weren't there and babies aren't moving much. What does this mean?