I know this is a controversial thing to say, but those "hand held" devices are usually super innaccurate!!! A couple of weeks ago, I went to a seminar on Exercise and Nutrition and they presented some information on how innaccurate even the calipers(which are better than the electrical hand held ones) were compared to underwater weighing. They presented some info on fat measurements taken on a female. I believe the electrical monitor said that she was around 25% fat, the calipers said she was 21% fat, and the hydrostatic method said she was 19% body fat.
So even if the doctors measurement were a little off, you're still in a good catorgory. The ACE table for Body Fat % puts you in the "fitness" catorgory which is really good. And BMI....don't EVEN get me started on that one. Even my personal training manual states that BMI cannot be used accurately on fit people. It doesn't take into account lean mass so if you are remotely fit or exercise on a regular basis, throw that "information" out the window. It's totally useless!!
cArolyn