Candybear, I don't SI, consider myself "normal" :-) and don't think you're a "freak and a head case". Too, I have a very good imagination.

I think a good doctor (and I'm sure you have picked one good for you) is going to be compassion personified like a good therapist is. I don't think a lie will "fool" them but only "worry" them more. I know you don't want to be "shamed" and are ashamed of yourself (not altogether within reason) but I think one way to help yourself with your feelings of shame and of being an "oddity" is to own up to it with the doctor. If you "need" to cut there you need to cut there! It is your body and you can cut there! But, being "sneaky" about it is not in keeping with it being you and your action. I would make a simple, true, "factual" statement and leave it at that. "I self injure and have done so where you are going to be examining. I would appreciate it if you could be as gentle as possible with me". Such words will elicit respect, I promise.