I think you are just nervous about the future, it happens, also because the surgery your organism can have huge stress, so don't worry you will be back on the good state and all will be fine, it often happens when you re changing too much in your life, also you mentioned that you were fantasizing about the operation, so this one of the bad parts what dream is live, missing the subject of fantasizing, you better to think about future not about that was done before. If you will feel uncomfortable and depressed next week visit this site and reach their online helpline https://www.andalahealth.com/condition/treatment-resistant-depression/.
