Susan,,Jeremy would probably have dropped off to sleep if he'd been lying on the floor. He must have been already jiggered after the harvesting,then supper. I doubt he had super-human strength at that age and the type of guy he was.
If he'd been a fitness fanatic,,then I might have been suspicious,,but he wasn't,,and certainly wouldn't have mustered up the energy to go on and kill 5 people.
Sorry-------------I don't buy it at all, for many reasons.