First of all, Carmen, that story is quite awesome and I will keep it in mind. However, I can't help thinking that a century or so back you might have been called a witch and... well.. you know the rest of the story. Nevertheless, thank you, I have a clue now of how to 'defend' against all this... stuff.
Stiros, by 'after picture' I actually meant after image (that is the correct ranslation) as explained here:
http://en.wikipedia.org/wiki/Afterimage
It was quite peculiar however as it seemed to throb in rhythm with my heartbeat. Maybe a special blood pressure actually pressured my eyes? Just looking for simple explanations here but why my circulation suddenly went awol is the good question then.