If you are doing some form of mock exam right now you're probably feeling a little bit stressed. A couple of things that might help a tiny little bit:
Mocks are TOOLS for your learning. They are not a judgment. Your grade in a mock is irrelevant but the comments you get are priceless. The trick is to use the mock as a way to identify the areas you need to work on. It may be a bit of content or it may be a particular skill. Either way, if you lost marks then it's a useful indicator of the work that needs to be done.
This is your opportunity to screw up. I remember vividly a very bright young woman coming out of her History exam with a confused look on her face. She had managed to miss the large booklet of sources that was provided along side the exam paper and had attempted to answer the questions without them. Unsurprisingly she didn't get a very high mark but it was a useful lesson for her and all her classmates about the importance of reading instructions! (NB: she got an E in the mock, an A* in the real thing - get the mistakes out of the way when it doesn't matter!)
Blank Page Fear is real, particularly for the longer questions. The trick here is about planning: draw mind-maps, annotate the question and generally get SOMETHING on the page and you will find that it becomes much easier to get started. Remember: something is always better than nothing.
It doesn't matter how anyone else does. I have fought for years against the idea of education as a competitive sport: it should not be and you can choose not involve yourself in such silliness. When you come out of the exam, don't engage in the inevitable post-mortem. Go home. Go for a run. Put on some music. Have a nap. There is nothing good that can come out of those conversations.
Everyone, EVERYONE improves on their mock. Of course they do. You have months more practice ahead of you - your abilities are not set in stone. This is just one step on the path to your final exam result.
If you are finding the pressure a bit much, do feel free to follow my new facebook pages which are there to support students who just need the odd bit of advice here and there. Click the buttons to find out more: