What Causes The Electric Shock Feeling All Over The Body?

Please dont laugh but i had a most weird feeling when i went to bed.
I had just started to close my eyes when i had a flash of white light where i felt like i was getting an electric shock to my system-pretty sure i heard a 'zap' noise.

I wasnt touching anything electrical and the electric blanket wasnt on.
I can be sure i wasnt dreaming it as it made me get out of bed pronto.

Am i losing it??? lol

Regards

Robert