My 46 year old self wishes that I could tell you the things it took me 46 years to learn. Like:
The path of least resistance is not the easiest path. The people who resist you as you try to move forward, or mock you because your progress is slow? Ignore them.
Don’t stop questioning or challenging or arguing. Those are all signs of intelligence, they are not character flaws. Not questioning and following blindly are character flaws. ‘Bossy’ is a compliment.
Take physics. Take math. Don’t drop-out of art. Don’t stop writing. They all matter, you are capable of them all, and they will all help you find your own happiness.
Those ideas you have about yourself, they are dreams, and dreams are not signs of weakness. Follow them. Pragmatism is not the be all and end all, and being pragmatic is not incompatible with ambition. You just need to find other people with dreams that will help you learn to fly.
You can go to university without a plan, the plan will come. Ignore all the dissenting voices who ask what job that degree will get you. The job will come. What you need is knowledge.
Don’t give into the pressure to define yourself in relation to others, ever. Nothing good can be kept in a box. Everything good grows and changes over time. You are too big to be defined. You are more than what you represent in other people’s eyes. Don’t be for them, be for you.
You are loveable and capable of inspiring love and loyalty, you just have to find people who are loving and loyal. When you find them, (and your 16 year old self has already found some of them) never let them go.