Mine said the same as yours.
Basically I think it's better to go off your BMI. Once you hit the Normal range for your height then start to look at getting to where you feel 'healthy' rather than thin, otherwise you can go too far, or alternatively, not far enough!
Putting it simply, I'm working down to 85, then down 70, 70 seems really tiny to me, but once I get there I'll re-assess my goal weight and see where I want to be. Ultimately I'd like to get to 60, but it all depends on how fit I feel and how good I think I look at the time. It's YOUR body, so make small goals for now and the closer you get to the major weight goal the more equipped you will be with how to guess what weight you want to be