Unsolved Mystery

I woke up on the wrong side of the bed this morning. 

LITERALLY. 

I woke up on my husband's side and he woke up on mine.

We have no idea how it happened. I rolled over and looked at him and then kinda growled, "What am I doing here?!" I thought maybe he went to the rest room, got too lazy upon his return and climbed in on my side. False. He never went to the restroom. He suspects that I steam-rollered him in the night. How do you not notice if you're being steam-rollered? I may be small but I'm not that small. I guess we'll never know.. 

{This is the usual routine... not last night tho}