WebMD states the worst time following your sleep deprived night will be first thing in the morning. That is when you'll feel it the most.
Remember, foggy brained friends, it gets better. Forge on into the day and just keep telling yourself that. You'll be more alert later.
Still, be cautious. Your brain will not be as sharp today. Remembering, alertness, decision making will all be somewhat impaired. So, drive carefully and navigate your day cautiously.
Good luck ... and tonight, go to bed early.