speaking as an EMT and firefighter with ten years experience, the look was unprofessional.
We did so much to try to create positive feelings and emotions in our patients and accident victims, things like banning mirrored sunglasses on calls, eliminating reflective surfaces in the trucks, keeping gawkers away and trying to maintain light conversation even if it was just between the responders, like we see this everyday pal, your injuries aren't that bad, if they were would we be talking about our gas milage or how many fish we caught last weekend?
My scars are all across my gut, one big zipper right up the middle that has been opened twice, and holes and bulges on both sides of my abdomen. I wear a t shirt swimming, I see the questioning stares when I am in public without a shirt on, I am used to explaining them to anyone that asks. I can only imagine how much harder it is for someone with facial scars, my sympathy and empathy to you.
Try to realise that the nurses would treat you better if they knew how you reacted to their expressions, maybe even consider writing a letter to help them realise what damage they did. I am sure they would try to do better if they knew that what they did was damaging to you. This is a learning opportunity, a foregiveness opportunity.