Tired of this misery

Before i start my post proper, i shall thank grace yong for making my cleanest uniform in the my wardrobe the dirtiest uniform now! THE STAIN IS PERMANENT!!! Now, i shall start my post proper. (It sounds like i am doing a debate...)
After so long, i still tired of life after all. Think through. I am only 15 years old and i am already tired of life... How am i going to continue my life until old. Sometimes, i think and think and maybe after all, i cannot be that long life. I am sick of it. I don't know why but i am blamed for nearly everything regardless if i am in school or at home. In school, for no reason, i get scolded and just a small little mistake i made, i seemed to be condemned for the rest of my life. At home, i do nothing, i get scolded, i do something also get scolded. There seem to be nothing in life that is worth for me to continue living for. I don't find it depressing anymore. I find it more of meaningless. Sometimes, i wish i could just cry out loud and let out of all these miseries but never can that happen. Everytime, we are educated to precious life but how to precious life if there is nothing in life that is worth to be precious? Once, a person taught me to consider whether my life is positive or negative. This person said, take out a while paper and use a pen to dot the paper. The dot i made is the negative thing that happened in my life. I know this is very familiar as that is what lawyer use to persuade a couple not to divorce. After dotting the paper, one will realise that the amount of dots are lesser than the white background. So, the proportion of white is greater than black which also means that life is more positive than negative. So in this case, we should precious life. After so long, i thought back and realise if i change it to such that the black dots represents the amount of positive thing that take place in my life than life will be more negative than positive. It is just the way i phrase it such that it will turn out to be negative or positive. But for now, i will use the second case instead. It seems like the proportion of negative is greater than positive. I can just think of less than 10 happiness that happened in my life but i can think of hundred and thousands of unhappiness in my life. Even when i think of the happiness, the unhappiness just suddenly pop out and cover off the happiness. In this case, how can i ever think of the happiness in life and how can my life me positive? I am tired and sick of this negative misery life. I am blamed for everything. I am always in fault for even something none of my business. Due to all of these, it just make me treat others badly. I have no idea why the hell am i blamed and why the hell did others like to take me as the target to be blamed for. I should "thank" these people for making hate life and regard life as meaningless. You think you are smart, i won't deny but due to your smartness, you push me to my ends! Stop scolding me for nothing, stop shouting at me when i just make a small mistake. NO HUMAN IS PERFECT! The worst of all is that i did nothing and i can still get scolded. It is totally ridiculous. The images of me getting scolded is currently repeating and repeating and repeating. I AM REALLY TIRED OF THIS FREAKING MISERY!!!