Are you a Russian doll?
Because you're full of yourself. See also Russian.
Here's the basic story. Once there was a prince who sucked his thumbs. His mother got so sick of it that she said, "If you suck on your thumbs ever again, you will not have no thumbs."
That night, the prince went into the dining room and sucked his thumbs.
Now he has no thumbs. See also Russian.