This the first problem that I see in your post.
I have consistently heard that calculus is very difficult for anyone who is shaky on any of the prerequisites. If you want to do well in calculus, then you need to have a very solid understanding of high school algebra, trigonometry, and precalculus. If you are weak at all in any of these prerequisites, then calculus is going to be tough. It is not enough to remember the formulae and be able to use them. You need to understand the concepts very solidly.
There is an even bigger problem here. The only students who should be this far ahead of the normal math progression are students who are very, very good in mathematics. However, these are exactly the same students who are very likely to use math quite a bit in the future. Calculus is a major key foundation for a LOT of classes that you are going to take in the future. This is not limited to math courses. For example you might note that calculus was originally invented to help with physics, and is still used a lot in physics.
It is only November. I think that you need to talk to your math teacher and your guidance counselor as soon as is possible. I think that you should consider dropping back to a less difficult math class.
If you do stick with precalculus, then you need to get a tutor, and you need to put a lot of effort into this class.
By the way, I did not take calculus until my freshman year of university. This did not stop me from getting a bachelor’s degree in mathematics from MIT.