I loved the twist at the end of this flash fiction story. You did a great job conveying a compelling story in just a couple hundred words, which is not easy to do. Well done!

The narrative where the protagonist seemed to be having an inner monologue with the reader in the first paragraph (where he wonders if the psychiatrist thinks he's even crazier than he himself does, and then the protagonist calmly discusses believing in vampires) undercuts the emotion of the rest of the piece, where the protagonist is fired up about this issue and borderline irrational. I would stick to one or the other (either logical or irrational) to avoid conflicting messaging in the story.

Overall, this was a short, fun read. Nice work!