Stress is not what makes you fail, it is the misconception that stress is a factor to failure. Studies shows stress is good for you and that you have a wrong perspective on it. Here a whole TED talk about it: (highly recommended you watch it)
#56 Word of Advice
What? You thought I’d tell you to go down there with twin hatchets choppin’ every thing you see? Well, sorry to disappoint but I can think rationally as well.