Hanging upside down is read as seeing life from a reversed perspective — confusion, or a sudden fresh view. Tradition links it to a period when the usual order is turned over.
When this appeared in your dream, what were you feeling?
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.