From his site:
"As I was writing the book, and in my work for the BBC, I began to feel a presence around me, like there was always someone in the room when there was not. It got to the point where I sat on the side of the bed in a hotel room in London in early 1990 and said to whoever or whatever: "If you are there will you please contact me because you are driving me up the wall."
Tin foil everybody!
I notice he doesn't mention his 'Son of God' days. I expect that's so that his reptilian followers don't think he's a kind of nutter!