Actually.
I just didn't understand the 2U paper, I studied like I normally did (which would be just doing past papers about 1-2 weeks beforehand since it was a smaller assessment) and whilst I easily understood the questions on those papers, the paper I had on the day was so difficult to interpret, especially the probability, and I think I was one of only a few who wasn't able to do well due to being confused.
I know this is why my 2U and 3U marks are so different because 3U was definitely much harder, but since the wording wasn't confusing, I was able to sit and think calmly on how to approach the question. Whereas in 2U, I had like a 30 minute panic session because I really didn't know what the teacher wanted from me. It was just bad on my part that I couldn't calm down and slowly approach the question as I was having a monologue going "OH GOD, DOES SHE WANT TWO CONSECUTIVE RACES OR ONE RACE AT A TIME? OH GOD. WHY CAN'T I DO THIS MAX-MIN QUESTION?"
But generally, Maths (both 2U and 3U) is my weakest subject, along with Physics. So I always overexerted on studying for those two. I'm a bit disappointed that I wasn't able to perform the very best I could in 2U, but my 3U obviously shows that it was just me being an idiot because 3U was the same topics + a few more and harder.