One thing I learned is that I can trust myself/body and shutting down is good! You don't have to "worry" that something bad will happen because you'll automatically shut down if it's too much for you. It's a reflexive action of sorts? Your eyes shut when someone throws something their way, you shut down psychologically when something is too much for you at the moment. It's not a bad thing, it will get less and less often as you begin to trust yourself and your T more and more.