I have had two events of this type in recent weeks.
The first was in a place to have a coffee and smoke. To the side I have views of a mountain and there are cows grazing.
These cows have a place to collect rainwater so that they can drink.
Well, the other day I suddenly realized that there are two places one near the other, where the cows can drink.
That I did not realize this, after months of going almost every day..., well, I usually meditate in the tranquility there so I do not rule it out, however, after months of going, suddenly there are two places excavated and with cattle tracks from many, many days.
The second was when I saw the Warcraft movie for the third or fourth time.
I was watching the movie and suddenly I see that the protagonist orc dies in his duel with the orc magician.
I did not remember this, I remember that the tribe saved the orc protagonist, not being able to bear the orc mage's transgressions to traditional honor.
I then thought that I confused this scene with the one of the human who defeats the orc magician. Could be...
But what he was absolutely sure he didn't remember is when his best friend ripped out one of his fangs from the now-dead protagonist ogre.
That was absolutely new for me and I'm surprised that I forgot something so symbolic, where the honor of the dead orc is honored in this way.
Also, there were a couple more scenes that I didn't remember, but that could be due to poor memory, since they are scenes without weight for the plot.
The funny thing in these cases is that one notices something strange and sometimes one is almost sure that something has changed...
But you can never be completely sure.