Interesting phrase of the day: social jetlag.
Essentially, what happens when your natural sleep rhythms are significantly off from the rhythms the routines of your life force on you. With effects that are apparently not dissimilar from the lag that comes from travelling through time zones.
Except it seems to take a 4 or 5 hour change before I notice travel jet lag, actually. Because domestic journeys don’t mess with my sleep much, only international ones do. So I’m not sure I’d even know if I were socially jetlagged.