I too am an emotional eater and I started eating emotionally in middle school. I am now 47, so I have quite a bit of experience with it. I will tell you that over time I discovered that I actually have a food addiction. It is much like any other addiction in that I use food to not feel my feelings. I tend to use food the most when I don't want to feel sadness, anxiousness, etc.
I have always had low self-esteem and a lack of self-worth and so I tend not to feel happy very often. For myself, my weight ended up becoming a big issue in my early twenties. I have always battled with the weight, but I really started putting the weight on at about that time. I did not identify what was going on with me then and eventually in my fourties I ended up having a gastric bypass to lose all the weight I had put on. I am glad that I did, as I am now at a much healthier weight, but it did nothing for the food addiction that I still have.
I would encourage you to explore the feelings that you are trying not to feel by maybe journaling things about your day. You can also choose to journal your food as the other person suggested, but I would at least start off just journaling your day. Journal as much about what happened during your day as you can remember and then write about how you feel about them. It helps a lot to put the thoughts going on in your head on to paper. This will keep your mind free of dwelling on those things that may be causing you to eat.
Have you spoken with your parents about this problem? Do you feel comfortable talking with them or with another family member or friend? I am not sure what type of things you feel down about, but you may even want to consider speaking with a counselor if you need some guidance. I would not be considering diet pills at this point. You are very young and that just could end up causing you health problems down the road, not to mention taking them will affect your mood even more.
Good luck and if I can be of any further support just drop me a note on here.
I am an emotional eater. I eat and eat and eat. Until about a month ago. I said no I'm not getting a bigger belly than the one I got. Put notes up for yourself. Explain to your parents that soda, desserts, and sugary things are not to be around to often. If you need a sugar fix, eat an apply or have some yogurt with honey. Set up an exercise program and stick to it. At the end of every week, set something fun to do. If you don't accomplish your goals for the week, you can't have that treat. Also, keep a food journal with what you've eaten, how much, your mood, and how you feel physically. Instead of cutting, wear a rubber band and snap it any time you have an impulse. Or you could squeeze an ice cube. Another thing I've done is coloring with red on my arm. Everyday, you wash it away just like the pain of that moment. And remember things get better. People love and believe in you. And even though you don't want to take pills, I didn't either, they really do help. I feel really horrible every time I don't take them. But know they don't make you hyperish happy. They level your mood and I found I could control my feelings more easily. I wish you the best of luck. Love!