What is the meaning of dreaming when you’re asleep and dreaming? You’re already dreaming, that you’e having a dream.
Your dream, nestled within another dream, is a way of telling you that the message is complex. It is not something that you would like to face and even your subconsciousness has to dress up the message as a dream within a dream.
Your dreams can be best understood by yourself, as the symbols and imagery are best deciphered by your knowledge.