A writer must always stick to a main idea when deveoping their story, as deviating from it might lead to a different theme in the end. Defining the construction of the main character is also important, given that its personality will define the significance of the turn of events once reaching the story's climax - which will determine the theme for the enterity of the story.
While we do not have the line 14 example, flinch generally describes a involuntary movement of the muscles to try to keep away from pain. For example, you would flinch and pull your hand away when in contact with boiling water.
