If you hadn't done it in real life some of the specific details would just be filled in by your imagination and you wouldn't know the diff.

In fact, even since you have done it there were assuredly things in your dream that were diff.

Like the time I dreamed about Smartt's mom masturbating with salad tongs. I only had to go into PTSD counseling for 6 months instead of the required 1 year when it happened in real life.