I think self-image is more of an issue than weight here.
You say nothing about exercising. It is entirely possible (particularly when you are young) to keep your weight on a fairly even keel by exercising. Talk to your doctor
. You will likely find that what you are eating is perfectly fine for maintenance if you also do some mild exercise.
I also question where you're getting all this diet info that you're reading all the time. There are a lot of women's magazines out there that give really conflicting advice, plus they push fashion and makeup in ways that tend to make women feel terrible about themselves. Recognize that the media might very well be a part of why you're feeling this way.