Definitely worth it. It might seem like a lot of money, and it pays off. I knew it was worth it at the time but my partner was very doubtful. Until we did it and he knew it was worth it. Better than health insurance because it gives you tools you can use forever! We did the HB, which is the US version of CB - not many accredited CB practitioners around when I did the course.
A good practitioner can not only teach you the techniques and give you the education, but will also help you with specific anxieties, like PP have said
Very normal to feel the way you do and it's fantastic that you are aware of what is available to you to help you with the birth!