No, you have a handler soft dog - you are not doing anything wrong, your dog is just very sensitive to you, and is mortified that he would do anything to upset you and earn your disapproval.
A dog can be a hard dog, and still be handler soft. My dog is like that. I do SchH/IPO, has been worked by police dog trainers, and all agree that he is a serious, hard dog. But since I've had him, I've done all his training on a flat collar (except protection training - the hard dog in him comes out when we do bite-work), or no collar, walk him easily on a loose leash, he is very mindful to be a 'good' dog.
Since your dog is so sensitive to you, I would ditch the prong collar, doesn't seem to need it when you handle him. Others, like your son, may still want to use it though.