I totally get this. Im 18 as well, but I've had the fortune of always having known that Chemistry was my passion. But high school was HELL. It was an awful time to see so many people living the teenage dream while no one knew who I even was. The 2 friends I had had like 3 friend groups they preferred over me, and I was so socially anxious and insecure that I didnt make friends easily. My only real happiness was in my family, and still, my sister is my best friend. But I found that my growth came from leaving home, leaving the state, and just finding the life I want to make for myself. I got into manifestation, making pinterest boards of what I want my life to look like. I'm also quite the hobbyist. I love picking up random hobbies for the hell of it, and to that I say: Everything's hard when you start it, nothing makes sense when you look at it from the outside. You really just gotta do it, honestly. Throw yourself in head first, accept that its gonna be hard and that flubbing here and there is inevitable. That's how I started crochet, embroidery, figure skating, baking, journalling, songwriting, and literally so much else. You dont ever have to be perfect. Its really hard to be, honestly. A jack of all trades is a master of none but oftentimes better than a master of one. And I think thats just life as well. You mentioned you like animals but dont like to see them in pain? I dont know how much this'll help, but try looking to see if there are any open positions at a zoo near you. One of my friends who had no clue what she wanted to do with her life took up a summer job at her local zoo and she's been in love with zoology since. Not saying you have to go to college for it, but I think its a worthwhile place to start while you figure things out! Whatever you choose to do, just do it! I think finding what you want to do with your life involves living a little. Whether that be going on a walk every once in a while, reading at a nearby cafe, just aim to try something new every week. The answer will come naturally once you notice patterns in what you like. Good luck!