My suggestion is to clearly put all the information you have in front of the doc /evaluator.
I second that. It took us two pediatrician visits to get a referral for anxiety, because I thought the problem was allergies and didn't mention the non-physical issues DD was having. I was also worried about leading down the wrong path, because I saw the emotional stuff as being a textbook indicator of [something I didn't care to have a diagnosis of, in large part because I didn't think it would have been accurate], but DD's doctor never even considered [that other thing].
This year, I'm trying the full disclosure tactic with teachers, too. It couldn't possibly be worse than last year, when we assumed (wrongly) that the teacher would rather figure DD out on her own. It was nervous-making to say, "DD has tendency X, which may make her competence level less obvious at school, [concrete example from the prior year]." But honestly, I'd rather the teacher understand what the issues are than attribute DD's occasional odd behavior to either not trying or "not that smart after all."
