Existential crises are not uncommon, and are in fact a sign that you're thinking out of the box to an extent. What you make of it is really up to you on an individual level, if you accept that on a macroscopic or at least societal level it really shouldn't matter or affect your lifestyle.
We had a whole thread about this topic on the Main board, actually, if you wanna bump it or just read about it.
Perceptions of Reality, it was called.