As someone who writes BDSM, I would agree with Mira. IMHO, a single spanking scene doesn't put a novel or novella into the BDSM category--but like Mira said, it ALL depends on that particular scene, what its purpose is, and what it accomplishes. I have a few questions for you that may spur further thought: Why did your publisher categorize your novella as BDSM? Did he or she think that would make it sell better? Or did they just not know how to categorize it? You might ask...just to get more information. How do you feel about the story? Would you characterize your theme as BDSM? How about your characters? Does the spanking create a desire to explore further (on the part of either the spanker or the spankee)? It doesn't sound, though, that your intent was to write a BDSM story, and I would go with your gut. Kudos to you about not wanting to misrepresent your story to readers.