P's clock lets me down

Guten Morgen! Heute ist es kalt. 

(Good morning! It's cold today.) It is cold, really frosty. J's hopes of getting snow and school closing are rising.

It was a strange morning. P has an internal clock which is almost never wrong ie he can tell what time it is without looking at the clock. I on the other hand have an internal clock which is almost never right. In seriously struggle to get anywhere on time ever. Normally in the mornings J wakes at 6.30 am, P sets his alarm for 7 am but usually wakes earlier and I just sort of slither into semi-consciousness. This morning I woke up and P said 'It's almost 7 o'clock' and I said'Oh no, why isn't J awake? He must be ill'. I went into the bathroom, banging the door and waking up J. Then I looked at the clock: 5.30! Had to persuade a grumpy J to go back to sleep.

What happened to your internal clock P?