What all falls under an eating disorder?

Heyy,

I wanted to ask you about when one speaks of an eating disorder.

Are you only affected if you consciously decide against eating or if you vomit it up again?

Or could it be that you consider food to be unimportant and forget about it, or that you simply cannot eat a healthy amount of food?

I am female, 15 years old and weigh 46kg.

I've never consciously forced myself to eat again or anything like that. But I still can't gain weight, even though I'm aware that I should eat more because my weight isn't ideal.

On the one hand, I am happy with my figure and feel good, but on the other hand, I think that my arms and legs are too thin and that I should gain weight.

I used to get insulted a lot because of my weight, I was called a "stock", "leek" or even anorexic, which sometimes hurt me a lot.

I'm starting to wonder why I can't gain weight, even though I really want to. I never get over 49 kg.

First of all, my mother, my grandparents, etc., are all of normal weight, maybe even a little overweight. My grandfather and my aunt are overweight.

I would really appreciate any advice!