yeah, that happens to me sometimes, too. I think SI is a way of dealing with extreme emotions, usually pain, that we just can't handle, and in my logic it makes sense that when we are feeling really really great our brain and body could want to respond to that extreme opposite feeling of just doing great in the same way it responds to immense emotional pain. It is just somehow too much. Our bodies are just so used to responding with SI urges it is embedded in our neural pathways as a response to any extreme, positive or difficult. Hope that doesn't sound too bizarre. Feel better!!