Learned the lesson of playing when tired

[Colima420]

I usually play 1-table SNG's at different sites. I am happy with my results so far. Yesterday however I commited the mistake of playing while I was tired. Needless to say, out of 9 SNG's I didn't place ITM once.
The interesting thing is that I know that due to variance, this is possible and everyone goes thru something like this. Nevertheless, what hurts me is that I noticed that I was doing things that I never do if not tired. I was doing plays that I consider really dumb.
When I play rested, I feel good. Even if I loose a game, it won't bother me if I played at a satisfying level. What bothered me about yesterday is that I could clearly realize that I was playing below my normal level and instead of just admitting to myself that I was tired and going to sleep, I kept playing.
Maybe something somethig similar has happened to some of you guys. So in the future, if I feel tired, I will not be playing.