On Thursday morning, I flew to Japan and arrived at Narita on Friday morning.
I stayed for two nights and left Narita on Sunday morning.
This trip was for my family (and getting some books to take back to the UK). It was really nice to see them and have dinner together. But my body clock was on UK time.
On the inbound flight back to England, I slept for the whole of the 10 hour-flight without having any meals. Maybe I was too tired.