u are taking too much pressure on urself to perform well thats what makes u nervous and not the exam itself. If the exam was itself responsible for ur nervousness then all ur fellow friends would have been here. Deep within u say to urself that it would be the end of ur career and make u a loser if u fail to perform . Nothing can be farther from truth. U feel awful not by this situation but by ur own view point that u take of it. So be realistic and replace ur illogical thought with a more rational thought.