Lately I’ve been inundated with things that are related to my primary fiction work. I’ll turn on a news program and they’re airing a story that has a direct link to my novel’s world. A friend will text me a piece of information ostensibly for some other purpose and it will fit neatly into place in my story.
It’s a very strange feeling, because it truly seems like the lines between that world in my head and the world outside of it are breaking down. It’s either madness or the very strange fuel that propels creativity forward.
I’ve always hated that stereotype of the author as a mad creature with a tenuous hold on reality. If anything an author has to consume much more reality than the average person. Telling people about whole worlds requires that one be observant of whole worlds. (Yet another reason most works by people under 35 have a lack of flavour.) So yes, you can’t be insane and still be a writer.
But perhaps you can feel a bit unmoored by the fluidity of it all.
Just Another Pretty Farce 
That’s just a sign that you are feeling very much at home in your fictional world and know how things work and fit together there. Which is a good thing.