Maybe you are making too big an issue of it all. She is way too young to understand what is going on. Keep life as normal as possible and don't keep going on about the move. However, of course, don't avoid the issue. Just mention it matter-of-fact, if necessary. Don't give her options about what she wants or when she wants to do something...relating to the move. They can't grasp what the implications might be. Children that age need you to guide them and make decisions for them. They don't need to have questions and options they don't understand, piled onto them.
For what it's worth, that's my opinion. We moved 3 times when the boys were little and never had any problems. Kids are much tougher than we give them credit for. Besides which, life is tough and as long as you are there for them, they'll learn to cope with changes.

Just to reassure, however, I agree that a trip to the doc is a good idea.

Good luck with it and the move.