I'm sorry about what happened! I hope everything will be okay and that her follow-up check up will be fine. I think it's better not to apply your own medicines or cream. Just follow whatever medicine was given by the doctor and change dressing if necessary.
I can understand your anger and frustration when your pediatrician said there is nothing he can do, as he is the one whom you consult your girl's health with. However, I dont't think he was obliged to calm you down in any way. Usually for doctors, if they are more "sympathetic" and offer words of comfort, I take it as a bonus but I dont't think it's part of their job. I think they've seen too many cases that they try not to show so much emotion anymore. I dont't think it's more important than his professionalism in my child's health.