THEORY 1: This sort of time loss is supposed to happen when you've been abducted and 'examined' by extra terrestrials. The less you can remember, the further they've 'probed.' You seem not to be able to remember anything untoward which has me worried that you may have been martian-buggered.
THEORY 2: You have clocks made by the same evil bastards who make clocks for high schools. We all know those things can run backwards. Fortunately I believe Dennis probably knows how to rig'em.