However, I understand your concern because starting anything at first is kind of scary. Especially since the students are used to one kind of teacher. This way maybe the students will be a little more accepting at first. I would look at it as an extension of student teaching. I will readily admit that it is a difficult job with many possible ramifications, but it is still a job and experience is still going to be a factor in how well one does it.
Many people change careers.
If you find that teaching does not suit you , then try something else. While teachers do have the ability to make a great deal of difference in a student's life, you are not going to be solely responsible for the breakdown of a student just because you did not do quite as well or quite as much as you would have liked to have done. It is still a job. A certain degree of anxiety may be useful, but if you feel that the lives of your students rest solely in your hands, then you are never going to make it through with your heart or mind still intact. Do you best and that is all that anyone has the right to ask of you.