Why is life so tough?

When I think of life I always end up thinking about all the bad times I've experienced . I think most teenagers might have the same problem. Whenever we think about our lives,the times that stay in our heads are the bad times−those annoying times where you could have done something right but didn’t.It's Too late to change something that could change your life forever, make it better in the blink of an eye. If we could only go back to that moment in time to kiss that boy or hold that door or even throw that trash away our life would be different. If I  could go back in time and change something that I think  would change my life ,it would be the day I would be a better me . I would go back to 2003, first grade. I started first grade like a menace, the person every kid would stay away from. If I had been a better person life wouldn't be as hard as it was for me when I was in elementary school. People wouldn't have been afraid of me and they would find me quite awesome. It would get a chance at something I have wanted my whole life−the chance to have friends that would stick by your side through thick or thin. There also very good moments that stay in our heads. The moments where you can't stop laughing or just can't stop smiling. Those are the moments that we should be thinking about all the good times of our  lives−the times that even make others happy.

What would you have done if you had the chance to change something you wish you  had done differently? Something you think that would improve you as a person,and change who you are today and make you a better you.

What would you do?