Anxiety and Insomnia. To have anxiety?

I am a Chartered Accountancy student and my exams are just about a week away. I'm having extreme anxiety since a few days as my exams are approaching, so I'm not able to sleep well. I do feel sleepy but whenever I go to bed, I feel throbbing in head, rush in the arms, stinging sensation in my body, shortness of breath and palpitations and I'm just not able to sleep. I have faced panic attacks 2-3 times earlier during my examinations. In that, I used to have severe headache, cervical pain, trembling in hands, sleeplessness, palpitations, nausea for a few hours and then vomiting whole night. I felt like I was about to die or something serious was going to happen to me. I'm worried if this happens again, I might wreck my exams. I really want to have sound sleep especially during these days to function well and study hard. Apart from the exams, I tend to have anxiety regarding things like a job interview, an important meeting, an important appointment or such things.