Stay organised using a consistent naming convention of your choice. You won't regret it.
Your questions can be used in different question sets, and both questions and question sets can be reused and copied over time. It is therefore important that you establish a consistent naming convention to make it easy to search and find relevant content. From the start, you should aim to give your content names that are meaningful and easy to use.
Question sets used as exams could be given names that contain both the course identifier(s) and the year/semester: "GEO100 autumn 2015".
Questions used in specific courses/semesters could be given names that contain information on a specific theme within a subject: "GEO100 autumn 2015 ice ages" or simply "Ice Ages".
It is not recommended to use contextual names such as "Question 1" or simply "13". This naming practice will over time result in a chaos of questions in the question bank.