Suddenly my guinea pig is standing still and acting weird?

i got milly almost 3 months ago now, i got her pregnant and the baby is now almost 3 weeks, she was fine few days ago but she lately freaks if i get her out, she hasnt been big on getting out but started opening up, now suddently i go her out and she purred here and there, but no sudden noises or petting and it seemed to be when i touched her back leg, she also stands still and shakes or will glare in my eyes, should i be worried? help ! im still kinda new and learning..