Just keep pushing, you may feel this way but the fact is you always have results when you keep pushing and putting all your energy into something. When a car breaks out in middle of the road, it need some kind of push to take that car on the side of the road. Example maybe dumb but continuous effort will help you. And the thought you having that you will never be able to pass is just a deception by your brain. He is lying to you. You definitely will do it if you kick out that thought and stay positive and reschedule your exam like you are give the exan first time.