When you try to read on how to conquer the dark sides of your self but somehow your dark self gets alarmed which leads to your heart getting tense instantly like if it was squeezed from inside. May be we need a better approach because trying to control or let express our deepest emotions may unleash nightmares. My concern goes with the need of a mentor or therapist. Regulating the flow of something unknown, extremely powerful, or very ancient may lead to an unexpected consequence. An explosion or implosion of some sort.