Mine did the same thing, the reason it is eventually turning off is because we have a battery saver feature that turns off lights and stuff that is left on (not the headlights). Sounds like the door switch is sticking might have gotten some dirt washed down on it when the car was being detailed. The door switch is located inside the door (at least mine was) on top of the latch not hard to change. I my case when I took the switch out to replace it the part store had given me the wrong switch and it was late so I sprayed some WD on it and freed it up, have not had a problem with it since.
EDIT: does it do it on both doors?
2013 GT Brembo Black, 3:73, 6-Speed, GT500's, Urethan Shift Bushing, 8 Ball Shifter, J&M LCA's & PHB, Eibach Pro springs