After enduring such a dreadful battle, you're supposed to feel elated. You're supposed to cheer in victory and feel relief wash over you as you finally can relax. Dahlia, however, didn't feel this way. She couldn't bring herself to feel anything positive at all.
Even as she told herself that the vampire was dead, all she found was that she was left with a sense of emptiness and something else: something that was growing. When the fight came to its abrupt halt, her adrenaline was still surging and the focus of the fight had distracted her, but now? She could feel her entire body shaking so uncontrollably that she doubted she could even walk or pick something up. It was as though her body refused to obey her.