I'm not sure I'd consider them dreams within dreams. I mean, when I'm having a dream which I 'wake up' from, but it's a false awakening, the first dream only becomes 'a dream within a dream' once the second dream has started. It's not that the dream was inside the other dream. It's more like, there were two dreams in a row. But in the second one, you have a memory of having the first one, and think it was a dream.