I'll second what Frog said.
We call nurses by their first names...I started out calling all the docs "Dr. whatever," and as I got to know them and be more comfortable, starting calling most of them by their first name. Our PA's go by their first names as well.
Go up to people, docs included, and introduce yourself as a new tech.
Make sure to ask questions when you don't know something (which you probably already know), and don't be afraid to offer to jump in and help!
Your prehospital experience will help you, and the ED experience will help you in school, as well as when you graduate.