help a girl out

hello!! ok so im in real trouble.

lately i’ve been on a diet in which i’ve lost a lot of weight, i know what you are going to say...”that i shouldn’t diet and lose so much weight (from 104 to 97.5lbs)”

but i like this and i feel great!! the problem is that people started noticing the weight loss and they started worrying i might be “sick”. even my parents told me that i look very thin. and i know that im underweight but i don’t want my parents to know because they are going to force me to get fat. and the problem is that in 2 days i am going to my yearly doctors appointment and there they are going to weigh me and see how im underweight and my mom will know too!! what can i do?!? i don’t want my mom to know.

(im 15 yrs old and 5”2 if that helps)