LOL tinks, thing though its not as simple as just height versus weight, theres your bone structure [build] to take into consideration, you are a small build so 9st would be a bit much on your frame. Im a meduim build so if i lost a st in weight than i am, & have done its makes me look anorexic cos all my bones would poke through even though i would not be anorexic or severely underweight but i'd look it - not nice, in fact no wonder i was ill a lot, now i know im healthier for a bit of padding
So i think if you look in proportion & can see your feet without bending over then thats fine you know yourself if you aint right unless you have unrealistic psychological views of your body.