Don't bother about bad stuff you did just learn from them and go on with your life.
I really don't like people who are sad for reasons that really doesn't matter. For example if a boy tell a girl that he loves her very much for a long time and wants to be with her and she reject him. This usually happens to a very young people at the start of their life. Well every time I hear something like that happens to my friend I always telling him it's not the end of your life. Maybe someday you will find the girl of your life but who cares. But now at the age of 20 it just doesn't matter.

We are young a we must live our life as young. To enjoy every single moment of your life. Do stuff that we can't do when we will be old. Do everything we want and if something doesn't work f*ck that, if something doesn't giving you a good feeling about yourself than f*ck that ! Just learn and go on. Don't ever regret of something, okay you have done bad but whatever just learn a go on. It's that simple. I know that love is a very hard feeling that we have to deal with but not in our young age. As Barney Stinson on How I Met Your Mother said: "When I get sad I stop being sad and be awesome instead." well it's true story indeed! So go out there and be happy and have fun till you are young !