Anti depressants. Please help me.

Long standing anxiety symptoms, derealisation and sleep problems, all the three symptoms respond well to Antidepressants. As a professional, I'd advise you to go ahead as your doctor suggested Medicines won't change what you think. But they modify the neurochemical milieu at Central nervous system, which in turn effects your mood, perception and thoughts. And thus, it'll help you to handle your thoughts. It would be beneficial to take combined therapy with medicines and psychological therapy. You would feel better by 6 weeks after the suitable medicine is given in a sufficient dose. But you have to understand that dealing with long standing anxiety is again a long term process. Be patient. Tips for board exams: relax. Make sure you eat properly and stay hydrated. Try deep breathing exercises for better sleep. Revise whatever you have already studied, and know that you have put in effort all this year, and that's going to influence the outcome, not these few couple of days!! Believe in yourself!! Good luck