I think that's normal hun, I've had a really good pregnancy this time around, and I STILL worry that my baby wont be healthy, I sometimes think the U/S lies etc.
All the best!
Extra blood work will tell them how to help you and your baby. Better to wait and see. I know its hard not to worry. I have spina bifida first degree. So its not bad, but it increases the risk of the baby having it by alot. Plus I'm GD and that in itself can cause a lot of problems. All I can say is I trust the people I chose for my OB group and I'm careful about my carb intake. They tell me some women don't call in with blood sugars or don't watch what they are eating. To me it doesn't make since I want what is best for my baby.