Missing some hours that I don't remember

Last Friday, I seem to be missing a few hours where I don’t really remember anything. I do remember working both of my jobs, then coming home and unpacking my lunchbox. But between coming home from work and waking up on Saturday morning, I have no memories. I’ve tried to remember my evening, but it has just disappeared. I do remember Thursday, Saturday, Sunday, but for some reason, I have lost the details from this night. I don’t even know if I remember going to sleep, or if I just assume that it was nighttime so I went to bed. I’m not sure how often this has happened, but it sure isn’t much fun! When I talked to my mom, she felt sad that I couldn’t remember part of my evening. My guess is the fog briefly rolled in!