I'm confused about what happened. Is she still feeling movement? If you get the feeling that things are not okay, you should call the OB. I don't think that anyone other than her doctor should be trying to move or change the baby's position.
Babies move around. Its normal. As for being small that is Just a guess. By multiple ultrasounds my daughter was measuring almost a month small and at 39 weeks was born at 1 oz short of 7 lbs. Bigger than my daughter who was measuring right on.