You are not a disappointment.
The fact that you can’t do your physics or calculus problems does not make you a failure. Teachers and parents make a big deal of your grades but a few years later it won’t matter at all, and certainly will not matter now you are grown up. You place so much emphasis on achieving those grades and making everyone else happy, but there is no need. Trust me on that.
Soon you’ll make your own decisions and you will realize that pursuing your interests and passions are more important than any grade or 8-figure income you receive.
If you want to write, study literature and history, you should defy all your seniors and do so. Honestly, redox actions have no relevance to leadership and people management in this real world, nor does momentum help you in your negotiation skills.
Do what you do best. Do what you like. Dwell not on those grades. You know in your heart what is it you want to do – insist on it.
It’s ok. You do not have to live up to anyone else’s expectations of you, and you do not need to feel you have disappointed them if you don’t do what they suggest.
You owe only to yourself.
Please change your course of study when you can. I don’t want you to end up like me 14 years later, and I don’t want you to have to go through depression and suicide attempts like I did, because you felt you have let the whole world down.
Write your poetry and your stories now, forget those math problems. Follow your heart. Don’t wait till you are 30 years old to do that.
Listen for once to your heart, and not your mind.
It’s ok, you are not a disappointment. Do what you love!