When is it ok to go back to the classroom?

So I have started my new job. The library is up and running. Students come in they have a lesson and they can check out books... and I still feel lost. There are so many things that I don't know how to do. I finally figured out (I think) how to add new books into the system, but I have a huge pile of books that need to be repaired or possibly taken out of the system. Where's the guide to all of this? So my question is, when can I move back into my classroom? Where students are mine, curriculum is mine and the space I teach in is mine. I never fully realized the scope of what needs to be accomplished in the library setting, the necessity of having to learn each grade level's curriculum in addition to the library curriculum, and the "school wide" feeling of what needs to be taken care of. Is it always so overwhelming to try something new?