It's funny how you remember a different ending to a story because I've had it happen to me at least twice. Are you a star wars aficionado? I swear there was a part where Yoda takes his walking stick and does a "whack a mole" version on a patch of mud that has little stick worms popping in and out. Maybe it's there in the movie and I just miss seeing it when I watch it but I swear I saw it.
I often "see" books I read. I watch characters as they progress in a book. Books become movies that I read. I'm very visual and so images and the inferred emotions of a book are remembered as if it happened. I've even experienced a sort of sleep walking - altho I didn't go anywhere but remained in bed. But I now understand how people can "see" things and avoid them as they sleep walk.
Maybe the trouble you have with reading your book, comes from the thought that someone "ordered" you to write it. You seem to infer that it was part of the experience of being hypnotized. Or you think so. I wouldn't like that either. Although it is interesting if it were true. A little experiment on you.
Or perhaps it is like this. There was a man that contracted a virus that caused him to believe that in every 20 minutes, he was just waking up. He wrote in a diary "I have just now woken up!" Followed by his experiences of those 20 minutes. Over and over it was written in this diary, but he never believed he had written the previous entries because his long term memory was affected. Memories that were stored in other parts of his brain, could be accessed. Like emotional memories of his wife. Also, if handed a baton and positioned in front of an orchestra, he could conduct them. (he had been a music conductor) So maybe this book, is like a memory you can't access and feel like it doesn't quite exist. Anyway, I like puzzles.