Does anybody here suffer with the ability to make stupid and random mistakes?

Since like 2020, my 2nd year at high school, I noticed that I started to make absolutely stupid and random mistakes at math. Before that, I had either good or bad score, dependent on my effort to learn it only. But since then, I wasn't able to stop making those mistakes...

I knew the topic, I knew how to solve the problem, I even did it.... But the numbers usially fcked up along the way somehow....

The range is quite large: from forgotten ² and - to straight out fking randomly changing numbers in the process of solving equations.... ( eg. was 21 and then below I just wrote 20 for no apparent reason whatsoever....)

Saddly, this continues somewhat until today, where I for example failed dynamics exam last week because of forgotten ² in kinetic energies in one line... 🥲. To be honest, I didn't fail just that- out of 4 problems, I had failed one, and one where I had made such numerical mistake. So if I did not fail the other problem, it wouldn't be an issue, but like this, it made me fail.

Does anybody experience anything simillar? That you can sucessfully solve dozen of problems without a mistake, and then suddenly at the exam, you fail so bad?

The worst part is- I don't feel stressed! I have literally 0 idea what's causing this! I am writing clearly and so on....

Not asking for tips, just curious if I'm "truly" the most clumsy student ever.... 😅 Maybe we can laugh together above our stories, who knows... 😄