The purpose of prayer is not to change God's mind, which always knows your wholeness and your deservingness. The purpose of prayer is to change your mind so you can see through the eyes of God.
The feeling, "this can't be it", is a very powerful form of prayer. It's the agony of the separated self longing for reunion with wholeness. It's the call of your soul urging you to return to your own path and purpose. It's the force of evolution driving you home. Do not try to deny or override your divine discontent. Heed its call. Knowing "this can't be it" implies that somewhere inside you, you DO know what IS it.