You could also die in your sleep tonight. Or, have done so last night. You didn't worry because it was out of your control and unpredictable. And being unconscious, you'd not have known anyway. Same, same. Stop worrying. Instead, spend some energy on gratitude that you have an EP working for you and you're in line for relief. That was my orientation. Or, worry if your affairs are not in order. Do you have a will? An executor? Those would be a far more productive spend of your time than worrying about eventualities with an exceedingly low probability...like 0.5%!! I was only worried about long-term effects, and in order to delay them or to stave them off entirely, I needed a heart spending as little time in AF as humanly possible. I am that human, and by God, I was going to have someone try to stem the tide of ectopy.

My wife and I have had to travel three times to Victoria, southern tip of Vancouver Island, to where the cath lab is at Royal Jubilee. Once for an angiogram in workups for the ablation, and then for two ablations (first one wiggled its way into the 25% failure-for-first-ablations category). We also travel every three months to see her oncologist and her rheumatologist, same area around Royal Jubilee Hospital. Now in normal sinus rhythm (NSR) for coming up to two years already, I can't begin to describe the relief and gratitude I have for the facilities and the wonderful medical staff and surgeons, and for the reduction in anxiety I now have. Also, I was highly symptomatic and felt awful in the last year that included both ablations. Truly awful. Now....amazing. I urge you to look forward to that orientation to your own eventual success.

You have every right to worry. We all handle our stress different ways. I don't worry until the night before and the morning of the procedure. Other people have a sense of dread when they are in Afib. They will give you detailed descriptions on how awful they feel. And they have a right to feel that way. I wouldn't tell someone to suck it up. We all handle pressure differently and the last thing I believe you do not need is some one telling all the reasons not to worry. This is hard to go through. And needless to say if your family is not available it is harder without your support system. These feeling are natural and not necessarily negative. They are what the are.
We are humans after all. What might be good is to remember is that you are doing this to increase the quality of your life as well as your life expectancy. These are the important issues to remember. You are taking care of yourself and that is a good thing. Many have gone before you and many will come after you. What is good is that modern technology has improved greatly in the last decade improving outcomes for many people. Expect to feel lousy when first waking up and that is normal. You might have some sensation in you chest because they have been working in there trying to fix your rhythm. But heal well and take every moment as it comes with as much good wishes and thoughts you can give to yourself as you can muster. Take care of yourself and I wish you the best. Good for you.