Fledgling by Octavia Butler

Octavia E. Butler's final novel is the story of an apparently young, amnesiac girl whose alarmingly unhuman needs and abilities lead her to a startling conclusion: She is in fact a genetically modified, 53-year-old vampire. Forced to discover what she can about her stolen former life, she must at the same time learn who wanted—and still wants—to destroy her and those she cares for, and how she can save herself.