Michael Berends All Kinds of Dolls

i have a 5 month old Baby Girl and she was 5 weeks preemie so the doc says coming to find out 10 other girls had their babys 5 weeks early at the same time i did is there any possibility that the woman who read the scan thing was wrong i felt my baby at 10 weeks rolling over in my tummy and everything else was very early too. another question is she is not grasping onto anything or rolling over i work with her so much on grasping and she still wont get the hang of it and she hates tummy time i put her on her tummy and she screams untill either i pick her up or roll her onto her back. tried everything plz help and tell me why everyone was 5 weeks early and if its a possibility she was on time