I eat the right foods with enough calories in to gain weight and I have been skinny for a couple of years but I moved in with my mum last year and was skinny when I came then after a couple of months I was gaining a little bit of weight near to a stone I put on and now I am losing weight really fast that my school trousers fall down and I don't Know what do do! Do I have an eating disorder? X

Sounds to me like you have a high metabolism. Nothing to fret, however, a visit to the doctor is always reassuring.

Sounds to me like you have a high metabolism. Nothing to fret, however, a visit to the doctor is always reassuring.

What is a high metabolism

Metabolism is usually based on genetics, some of us have low metabolism, some have high.

Metabolism is : the sum of the physical and chemical processes in an organism by which its material substance is produced, maintained, and destroyed, and by which energy is made available.

The organism being you.
And
Material substance is your fat.

Having a high metabolism means your body burns fat at a higher rate, with a small diet you can lose weight much faster than those with a low metabolism, because someone with a low metabolism will burn fat much slower.

OK but what are doctors meant to do

They'll be able to take tests and find out if that's what really is going on, and give advice on how to control it.