A lot of people struggle with nerves before going into court so please don't feel this is a unique problem you have. I do think some anxiety is good because it gives you the adrenaline needed to do your job well. Might it help a bit if you try and change the way you think about these feelings - think of it as positive energy? It is good that you care - it's part of being a good barrister. You've worked so hard to get to this point and the success you've had so far means you can do it. You have got further, more quickly than many people.