If you get into a situation where you disagree with a doctor or nurse (you will), pack the patient and go to the rig. Then you are in charge and they can back off.
A few good pieces of advice. Never be afraid to ask questions. The only dumb question is the one you don't ask. Always be open minded to new ways of doing things. Every medic has a way of doing things and you can learn new ways and incorporate them into your unique style. This a career where you never quit learning. So if you ever get to a point where you think you know everything there is to know about EMS, then take a step back and re-evaluate .