In my defence, it's been a tough week. My daughter has been finishing her Design Technology project - 60% of the marks for her GCSE - and the tension has been wild.
Meanwhile my son has been ploughing through his A2 coursework.
It was all so different when I was at school. All we did was face a wall of exams in June. This felt, at the time, like taking a deep breath and jumping off a cliff. But maybe it was better than endless modules and re-takes.
So on Saturday night our exhausted teenagers stayed in while we went out. I can't remember the last time this happened. It was probably back in the mists of time when Nick Clegg was still popular. We left them sprawled on the sofa surrounded by chocolate while we went off to meet up with some old friends - friends I'd got to know when I was 18 myself.
You behave very differently with people you've known all your life. You don't bother with all the layers of polite chat. Within half an hour of arriving, I was having arguments about whether the student who threw the fire extinguisher from the roof should have been jailed, and why we pay so much tax. I forgot to be responsible and respectable. I kept nodding when anyone wanted to refill my glass.
So when we got back home, where teenagers and cats were lying half-asleep in front of Casino Royale, I have to admit that even Daniel Craig's brilliant blue eyes looked slightly blurred.
'Good time?' said my 18-year-old, grinning.
There was no point in trying to brazen it out.
'I think,' I said humbly, 'I might have drunk too much.'
So that's my credibility blown. It's very hard to lay down rules about sensible behaviour when you break them all yourself.
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