congrats! Hope the job meets all your expectations. I love having ER tchs available, makes my job so much easier. Some advice, know what you are allowed to do, and what you are not. As an EMT you were able to do lots that you can't do in the ER as a tech - the RN's can't do some of the things you did as an EMT. I mention this because I have observed RN's and Docs that will ask tech's that they know have your background to do skills they can do in the field, but not in the hospital. It created lots of stress for the tech, who wanted to be helpful, but didn't want to lose a job, and sometimes, I hate to say, it pissed off the people asking for help when the tech said "no, I can't do that here".
As an ER nurse I try to utilize the tech for task that they are qualified to do, while I do tasks that they cannot. Also, be willing to do the jobs asked of you without attitude, sometimes the nurse is asking you to do a job that she or he could do, but has lots of other tasks waiting that only another RN could do. I hate hearing, why don't you do that yourself, or what are you going to be doing? I don't always have time to explain everything, althogh if I do have time I like to say, "please do X, while I do Y." But if you do see nurses trying to have you do all there stuff cause they are lazy, call them on it, or go over their heads. Everyone that must work with them will appreciate it, and have probably already pointed it out to the manager.
Last piece of advice, never go to work without your sense of humor. As an EMT you have seen JOHN Q at his best, so you understand what I mean.
Again, Congrats, I know you will love it, I know i love working in the ER, everyday is different.