No, I never had any nightmares. However, I’ve been an insomniac ever since I was a little kid and, instead of counting sheep, I would try to relax my mind by naming the Presidents in my head in chronological order, then each President’s birthdate, and then each President’s date of death. It’s how I actually memorized all that information when I was younger. Then I moved on to Vice Presidents. Looking back, I realize that I was a pretty weird little kid.
Unfortunately, that doesn’t work anymore, so I’m just stuck with 3-to-5 hours of sleep at most each night, whether I count Presidents or Vice Presidents or not.