Why are we even here, reflection of life?

So this is kind of a reflection question. More of a way for me to express my feelings. I only request educated and productive answers from people who are interested in having an educated conversation. So anyways, i am 14 years old, i've always thought of my self as a down to earth individual, and fairly smart regardless of my grades. I have a fair amount of friends and i am adjusting to high school. Anyways...i am pretty interested in designing weapons (preferably non lethal) for the military hopefully at a company like rathion. But lately i have been interested in the universe. I have also been under a large amount of stress lately since my brother got in trouble with marijuana at school and my parents are suspecting me of smoking, as well as a rumor went around that i was selling and they didn't quite believe me because a teacher told someone, Its pretty complicated. I think i am getting to the main point of this article, i have also been interested in the universe lately and i have begun thinking. How am i relevant? no matter what happens, earth isn't at all apart of anything in the universe. If it disappeared, no one would know. Were so unimportant as 3 billion people, whats one person? Im not at all talking on a suicidal level..so don't worry, or yze. Im just saying, looking at proposed maps of the universe, were so unimportant regardless of whats out there were not even a hundred billionth of the head of a pin on the map. Im just reflecting here, and where i want to be wealthy, get married, have children, and most of all make a difference in this world. Lately, when things get to much, i have just been thinking, why does it even matter? Im so irrelevant its not like a parent accusing a son of illicit activities has any effect on the universe. You know? Im wondering why other people dot feel this way. Or do they..? Thats just a little of reflection. Sorry for any grammatical errors i kinda just pumped this out in a hurry.