If this were my dream, I'd think of the top floor as my thinking and the bottom as my feelings and emotions. That I got off "early" and there was an explosion, etc. would get me thinking whether I was afraid of my emotions and thought they might damage others or be too much for my therapist, etc. That the elevator exploded, I would think of anger and see if I had an anger issue? Maybe I'm working on my anger but can't quite "defuse" it as I would like to, I still feel it causes mayhem and kills those around me.