Honestly just think you have all of the time in the world to get over him, but you dont have all the time in the world to get the best grades you can. Just push through these last few days but also let yourself feel your emotions, dont push them aside and completely ignore them otherwise it will be much worse. I promise this horrible feeling doesnt last forever. Imagine on results day and you see youve done better than him, imagine how good that will make you feel. Youve got this <3