Hey crazychicksj!
I have learned recently, (still in school until December) that when you move into a professional theatre (of any size) you need to think of things a little differently. I found that inter-personal communication is a little different and you need to keep your professional face on the majority of the time. I also learned as I SM-ed my first big show out side of school (this June) is that I was more prepared than I thought. I feel that my education and experience at school really acted as a professional production team and prepared me beyond anything I could have thought. As I jumped in and pushed through the confidence I held in school came back and acted as confidence in myself as a professional. Also by allowing myself to be confident and as I stood up for myself, my production team and cast looked at me as a professional and after tech admitted that they forgot I was still in school.
That was long winded and probably redundant so to close - Take all you have learned and let your self learn more. Once you get your footing in your new company let your confidence show and they will respect you and all that you do.
You are ready! Don't let anyone (or yourself!) tell you otherwise
And never forget that we are all here for you if you ever get stumped or need to vent.