I left the exam just after half time because I was very frustrated

the problem is that I was completely lost during that exam, I mean I read all the questions and there was no one that I could answer it, even the first question, the simplest which has only 2 points I tried but I couldn't answer it, I was in big stress, personally I thought that it will be better for me to left the exam because I thought that I need to break to end that stress, and personally I sayed to myself that there is still a lot of other exams next week's that I could greatly work on them to compensate that exam

Note that I'm not saying that what am talking is necessarily right, nor that what you are saying is false, but I've just done what I thought it was good to me, and sorry if my message was a little violent, am just trying to get help