Possible eating disorder? Everything's heading downhill.

I am a 16 old girl, going on 17 pretty soon. My whole life I've been told my body is perfect, I don't need to worry about my weight, I'm beautiful the way I am, I don't need to change. Unfortunately it's so hard to let my mind agree with that.. and I'm sure many teenagers struggling with weight can agree. It's not easy listening to what people say, because there's always that one voice at the back of my mind saying "Oh they're just saying that to make me feel better about myself". I'm 5'7, and now 135 lbs. Some days I look at my body in the mirror and just pick out the worst things about it such as my thighs, waste size, stomach flab, and arm flab. I am part aboriginal, and looking at majority of my kind, most of them are over weight. I always think to myself I don't want to become like that, but then again I fear I have already reached that point. Ever since around grade 8 is when I started becoming uncomfortable about my weight. I've never found my body beautiful. I want to be skinny, thin, 110 lbs, even less if possible. In the past about 3 months ago is when I started eating everything I could, then going to the bathroom and bringing it all back up. I couldn't help myself. The days I wasn't able to do that, I'd just starve. I wouldn't care. My throat became so sore, I stopped for a while. My life is very stressful. And I do know that people just throw that word around, but if you knew what was going on around me, and heard every thought that crossed my mind, you would probably be in tears. I got so fed up with everyone, including myself. Wondering why I couldn't just be skinny and not fat. 3 1/2 weeks ago I was 155 lbs. I've cut back my eating so much, that one regular dinner meal would probably last me 1 week. I've become so upset with my weight that I purposely prevented myself from eating. It started off as not eating breakfast or lunch throughout the whole past school year, and just eating a lot at dinner. I've made myself go hangout with friends during the evening so that I wouldn't be home for dinner. I never brought money with me so I didn't but food. I never accepted food either. Still don't. I tell my parents and family that I am on a gluten free diet, and that's why I can't eat most of the food they're eating. Whenever I feel stomach pains from being so hungry, I will go for a smoke to forget about it, or if that doesn't work, I will take 2 bites of an apple to make myself feel full. Or, I will eat a small amount of blueberries, as they can be used to boost metabolism. If I need to distract myself from food, I go workout. All I drink is water only every now and then when I feel light headed or shaky. Even weak. I lost 20 lbs in 3 1/2 weeks. No one knows about this, but my parents are noticing weight loss. They do think its from my "Gluten free diet", and exercising. In a way, I feel happy about my wight loss success, but I'm also ashamed because I'm not sure if these are signs of an eating disorder.. I'm sure they are, but I don't know if they're that serious. I love food. I work in high end kitchens. But I feel so much regret when I eat a meal. I know I should be eating more, but I'm scared, literally. I panic when I feel I ate too much. I freak out when I eat over half an apple. I'm becoming more afraid of gaining weight, and becoming more terrified of eating. I still continue doing all of these things, and I think I might until I reach my goal, or if I'm able to exceed my goal. I don't want to eat more, as I fear the littlest pieces of food will bloat me, make me look fat. But the thing that irritates me the most is how my body is reacting to it. I'm always so tired, because I can't sleep at night. For the past month I haven't been able to sleep until 3am. My body starts shaking when I stand too long, I always have gut pains if I over eat compared to the little amount I consume every now and then. I'm always becoming more cold, even in the warmest temperatures. I also get really big headaches. And also, if I get up to fast, I'll start to feel like im going to pass out. Everything starts spinning, and then things get blurry. I do have a feeling its from the lack of nutrition, but I can't bring myself to eat anything else. Another thing is, I do smoke weed. More often than you would think. Instead of eating when I have the 'munchies', I distract myself by doing something active. How do I get rid of the pains without eating more. Someone please give me as much feedback as possible. And thank you for taking the time to read my Note.