Night shift and cognitive function

I've been night shift (6-6) for about 2 weeks now. This is my first time ever working late PM hours as I've only ever worked jobs that required very early morning starts. I learnt very quickly that flipping sleep schedules back and forth was not going to work for me, and now I stay awake every night and sleep 6 hours from mid morning to noon-ish.

Regardless of how many hours of sleep I get, the "brain fog" switch gets flipped on around midnight, peaks around 0130, and only mildly improves around 0400. This seems to occur regardless of sleep/rest, caffeine intake, diet, or pace of he shift.

To those who work nights, is this normal? And does it become less severe with time?

To those who are natural "night owls", do you feel this at all?