did your dog heel? did she still seem energetic? if yes to both then bring her back and let the trainer work. being open minded is your best friend.
coming from an open minded person and one that has used and will continue to use a prong collar, if YOU aren't happy with how training is going I absolutely would not go back. I don't care how happy and energetic a puppy is, I see zero reason to use a pinch collar to teach heeling anyway.
use a pinch on a dog that has a good foundation and they learn consequence for actions they already know. Use a pinch to keep a position it hasn't had any foundation or learning in and all you do is create a dog more worried about leaving your side than performing a behavior.
If all you ask your dog to do is heel and not much else, then all is good. If you tend to move on further and have a dog that will work in unison and on it's own and not be worried about making a wrong step, the future holds a lot more learning potential when you use a pinch after a foundation is layed, not to limit behavior it hasn't learned yet.