Hi ! I do not know what has caused you this fear , but I will suggest you to control your emotions, and concentrate in your examinations which is just 2 days away. However, if your emotions are that much affected that you can not even think of appearing at the examination, then I would suggest you to see a Psychiatrist
on an urgent basis who may counsel you on your condition apart from giving some medications. So take care. WIshing you all the best for your examinations.