I recently began an exciting position in a new institution after an eight year stint in a previous job. What a massive difference: it has been an intense learning experience after knowing my previous role inside out to starting afresh. But it has been hugely enjoyable and I have a few hints and tips that I have picked up along the way.
When you have been in a position long term, many aspects of the job become second nature. It is easy to forget that you need to learn EVERYTHING all over again: from who to contact for what, to who can help you with specific queries, not to mention learning as much as possible about an institution. Stay calm. No-one will expect you to be doing the job without having researched and taken in information about the organisation and how you fit into it.