I know exactly know how you feel. Sitting in front of a computer for a very very long time can make you think about... what you are and what are you going to be.
I'm 17 years old. All I was doing was playing games, lurking in the internet and wikipedia and stuff like that. The only times I was exposed to sunlight, when I was on the road going to the school. I was dreaming to become a psychologist who unlocks the mysteries of the human mind but I suck at maths and I need to know maths to pass the tests to become a psychologist.
It's summer now. I'm drinking with my friends most of the time. Socialising will make you know yourself better. You start to laugh at everything if you are drunk with your best friend. We lived a lot of crazy things that no one would believe. I'm at the home for only like 5 hours (excluding the time I sleep) each day. Also just 4.5 hours ago, I drank about 5 glasses of vodka, mixed with energy drink because it smells like medicine and tastes like cologne but it's tastes okay with the energy drink. So don't pay attention to much about what I'm writing here.
We all will die one day and to most people leaving a mark in the world before dieing is important. I say just live the life. Living the life is pretty impossible for me because I'm only 17 but I really want to travel the world when I grow up. I don't want to travel to Paris, Tokyo, New York or anything like that. I want to see the Amazon Rainforest, Mount Everest, Caribbeans and other interesting places. Not touristic places where everybody goes.
I know that I will probably never travel the world. I'm not unique. I'll get married and get lost in the world like everybody. Thoughts like these happens in adolescence. You actually don't feel like you are the center of the world in adolescence like most psychologists say. You just think you are GOING TO BE the center of the world one day. You think you are going to be unique. This however, won't happen. I will probably be very depressed about "What kind of dreams and goals I had and what kind of life I'm living now? What happened to 17-year-old-me?" issue when I'm in my forties.
My suggestion: If you have a dream, try to do it. If you don't succed you will eventually find yourself another goal. If you succeed, you might even become the next Leonardo Da Vinci, Albert Einstein, Beethoven. If you give up on a dream because you think it's difficult, like how I gave up with psychology, don't give up. Because you will regret it each day of your whole life. If you don't have a dream... Well, you will have one eventually