Distraction Before a Session

My girlfriend and I have an appointment in a few weeks with a Mistress. It is a first for both of us. It is all I can think about. I don't want overthinking all of the possibilities to blow it for me. I'm trying to walk in with an open mind, not hoping for anything but a good time. Is it common to overthink a session weeks before it is scheduled? Have you found this could hinder the experience?

My advice to fantasize if you feel like. If the session is good and the chemistry is there, the experience will blow your mind. Although you shouldn't send a ton of pre session emails to the Mistress, it wouldn't hurt to let her know how you are feeling. Maybe she will have some pre session instructions for the two of you.