I Am Very Often Stressed Yet Im So Young

So many people tell me that I don't even know what stress really is. I may only be 19, but even I get stressed and it is more often than you would think. I always am worrying and freaking out. If it isn't about grades it's about my family or friends, or just even myself sometimes. I have got so much coming up right now along with a couple of family issues, it just feels like it is just getting to be too much. I just don't know any good ways to deal with stress in a good way -_-