I am 18 years old. I am a student. I do not understand my condition. I have very important exams. I used to get good marks constantly and then everything turned up against me now. I prepare my best, but I do very badly in my exams. I am feeling hopeless. Even after studying 8 hours daily, I am getting very low marks. I am completely puzzled. Why does my brain get numb during exam? I have lost all my confidence. Please help.