I am sad/depressed and i don't know what to do.?

Your last sentence says it all g-funk. Call 1-800-273-8255 immediately. Just talk to them about everything that is going on in your life. Be honest and you can get help. I have had thoughts like those myself and I know the hardest part is finding the right help. My best suggestion is to just talk it out with someone you have had no previous connection with and realize that there are people out there who don't even know you exist but care very deeply. If you don't get help, and seriously call the number it can make a huge difference, you may not be strong enough to change it on your own. Also I seriously suggest talking to your loved ones about it. If they love you they will help you no matter what, But first call the number man.