Hun, you have every right to be afraid and worried! It is not something you can just switch off because someone tells you to. I even had my counsellor tell me to "just get over it", yeah great job she did!
My advice is to try to find comforting and supportive people who will listen to your concerns and understand your feelings. They are hard to come by but even if these people are in the online world on here, at least you will have some virtual ears to listen to you.
Also, try to have as much control over this birth as possible. Write a birth plan, book in for a c-section if you feel that would help, organise positive support people, etc. That way hopefully you will feel a bit less anxious about it.
Feel free to pm me anytime if you want to chat