I'm not sure, there could be obsession about revisiting this, or, it could just be you trying to somehow "solve" this mystery by revisiting and the trigger could be accidental.

There is such thing as neurons in the brain getting fatigued by constant firing. If the neuron has to do the same thing over and over it will finally "decide" that something is wrong and tries to protect itself by firing much less.

Everyone I think have felt this, we've thought of a word and then we think of it more and more until it seems strange, like has it always been like that, what a weird combination of sounds/letters, and going further feeling, that can't really be a word! It is because we expose the brain to this word over and over in such a similar way that the neurons start to fire less. The result of firing less is the emotion of strangeness and not getting a full experience of reality.

The "cure" is not to think about it more, but to think about it less. Thinking about it less will make neurons fire with their natural flow.

Everyone has different thresholds for this kind of fatigue. If you have a low threshold you will have these moments more frequently. If you simply cannot stay away from dwelling on things, maybe then you need to ask a therapist.