On my 3DS I used to but that was because I was supposed to be sleeping anyway. I could even listen to music on the radio and 3DS earbuds and still fall asleep at times. Now if I feel like I'm tired I save and go straight to bed.
This isn't something that has happened to me before. I think there are times when you get bored and tired when playing a game, but I've always just turned it off instead of continuing to play it.