Just consider it a bit of professional concern. Even vampires can go through the horrible effects of exhaustion. I wouldn't want you to start hallucinating or anything on us, after all.

[ She tries to say it like a slightly amusing joke, but it was a legitimate concern. Sleep deprivation and exhaustion could cause so many problems. While she was a novice, her experience in the medical field was substantial enough to feel comfortable in saying 'professional concern.' Just... Ignore how young she was. You're never too young to learn what kind of mistakes could happen because someone hasn't had a good rest in a long while. ]