The medical definition of anorexia nervosa requires a BMI under 17. In other words, anorexia can be a symptom ("I'm not hungry"), but if you're saying that you're an anorexic, or that you have the disorder "Anorexia," then it is required that you have a BMI under 17, just as rigidly as requiring a certain blood pressure for a diagnosis of hypertension. You're not anorexic. Get over yourself.