My baby is 8nmnths, 5mnths corrected age (3 mnth premature) and she has begun rolling over. After she does this she is almost instantly angry because she is stationary. She kicks her little legs in the air and flails her arms in the air, I call it swimming lol, but she doesn't connect them to the floor so she gets very upset. How can I get her to start leaving her limbs on the floor to start movin??