Have you started any new medications? Are you under a lot of stress?

I experienced time loss during a time of really high stress a few years ago, but I would completely forget events - I emailed a professor in a panic because I thought I had forgotten to write a test, and the professor replied to tell me I wrote it. Around the same time, I was scheduled for an EEG, and I don't remember it at all, which is abnormal, usually I remember medical tests clearly. But I obviously had it done because my doctor got the results.

You could talk to your doctor about it, I'm sure they'd know better what could be going on than we do.