I feel like I am gargling razor blades, I always get them during exam period and other stressful times?
It has been proven that stress can have a direct effect on your health, which means you might want to take even better care of yourself during exam times or other stressful periods. Even things such as eating healthier foods, getting a reasonable amount of sleep every night, laying off alcohol, taking relaxing baths etc.. could really help. here are a few links with ideas to reduce your stress induced illness from occuring in the first place:
Try to pinpoint exactly what causes your stress, and see if there is any way you could reduce it. If you're feeling severely stressed out, it might even be worth talking to a counsellor or other trustworthy figure to help reduce the strain.
I will say, that a sore throat that severe isn't healthy. If it's recurring you might want to get it checked out by your GP just to make sure you don't have something like tonsillitis. Although your stress is probably contributing whatever your problem is, it's always worth checking that there aren't any health factors involved.
Hope that helps, and that you manage to conquer your sore throat and stress