Hi! Firstly, let me say that I completely understand your fears and anxiety over the extraction-it's a big deal in one way! I too have dental and health anxiety and know exactly how my mind runs wild whenever I have to face similar issues. I imagine the worst case scenario that could happen etc
The thing is you are in very good hands, very safe hands too. They wouldn't give you GA if your health wasn't up to it, you will be absolutely fine?
Try to focus on how good it will feel to not have to worry over that tooth anymore, to not have the pain and anxiety that comes with it. From tomorrow, you are free of all the anxiety and pain of that tooth.
You are braver than you think because even though you are anxious about having this procedure, you're going ahead anyway-that's pretty courageous!
Please feel free to vent as much as you like on here and keep us updated! What time is your procedure going to happen?