Some sound advice from the Good Retreat Guide

Is this spirituality just stuff inside my head ?

Going on retreat is not necessarily about having a spirituality. You might have one but most people don’t. It is about refreshing yourself, relaxing, and taking a journey into the deeper self. Reassessment about your life and relationships and values can happen. And why not? What other time have you ever had to do it?

It does not matter how many spirituality books you have read or how many self-development courses you have attended or what spiritual techniques you have practiced for deepening your inner awareness. Unless you stop and let go of your ordinary concerns, the spirit can not speak to you. The present moment is where the spirit lives so you have to let go of yesterday and cease to look toward tomorrow which has not yet arrived. You need to stay in the present moment long enough to listen to your inner spiritual voice. Be like the flowers in the field, Jesus told us. They do not worry about this or that but just live. The Buddhist say that this state is the place of reality. Going on retreat gives you a chance to explore these dimensions of yourself. Not in your head but in your soul.

http://www.thegoodretreatguide.com/help/topquestions.html