Posted this on /adv/ but I feel this will get better replies here.
I don't have much trouble understanding concepts because it's pretty simple, basic math (calc 1), but I seem to have a spectacular ability to commit the most stupid errors.

My performance in the last exams definitely doesn't match my knowledge/capacity.
Hell, I'm positively sure there are people that have taken the exact same exams I took and scored better than I did just because they did follow their formulas correctly and not because they actually do understand what they're doing better than I did.

I do know the stuff, but I simply fuck up. Once I'm given the exam back, I see the errors and I can understand why it's wrong right off the bat. But in the moment I'm taking the exam I'm totally oblivious to the fact that I'm doing things wrong. Even when re-reading multiple times what I did before handing in my exam, errors go unnoticed to me.
Does anyone else have this problem? How do you overcome this? It's frustrating.
Generally I'm not bad at math but lately my efficiency has been pretty low.