Levelling up stands for growth that finally shows. Dream books read it as recognition of effort, the sense that you have moved past a stage that held you for a while.
Has this come up in your dreams before? What was going on in your life then?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.