As you are new to flying, although you have done the training, it is all still very new and alien to you. What you lack at the moment is experience, in time your experience will give you confidence as you encounter and learn to conquer various testing situations. For the time being, just hang on in there, be as professional as you can at this stage, and learn from your experience. It will get better as you continue to develop. Finally, a lot of young pilots will be in the same 'boat' as you, and your feelings and thaughts are quite natural and healthy. Good luck.