@Lagomorph: I've done something like that. My eyesight is always getting worse and I used to be able to read my clock without my glasses from my bed. But this one morning I woke up and looked at the clock. It read 8:30am. 10 minutes before school started.
I literally jumped out of bed, ran around like an idiot and got dressed.
Only when I put my glasses on I realised it said 7:30 >.<