BBB, being frightened of surgery is TOTALLY NORMAL. I had a planned CS 9 days ago and I was still peeing my pants the night before thinking about it!
However, unlikely thought it is to happen, being forearmed is very empowering. Do you have a birth plan? You could, if you wanted, always include a wee section 'in the event of a CS' and write in what you would like to happen. Don't forget to have it written down that you are frightened too. I did in mine and the theatre staff were wonderful - holding my hand, explaining absolutely everything.
I can reassure you that the spinal anaesthetic blocks ALL of your pain and they test you vigorously before they open you up.
My story (in quite some detail ) is in the birth announcements if that's any help.
I have no experience of a conventional birth, but it seems the more relaxed you are, the less likely you are to need intervention. So maybe find out what a CS involves, include your wishes in the birth plan - then FORGET about it, and focus on your birth
Whatever happens, when you get your wee bundle in your arms - it's all worth it. If you do feel traumatised, don't forget to talk, talk, talk, to anyone who'll listen!
Best of luck xxxxxx