I dreamt that I'd used my laptop to record the start of my sleep before my nap, but then when I woke up I couldn't figure out where I'd left it. I looked everywhere in the house, and found all sorts of long lost items, but my laptop was nowhere to be found.

I remember thinking "Ten minutes have gone by already, I really need to record the end of my sleep or it won't be very accurate." I realised I could use another device (such as my phone) to do it, but I really wanted to end it on the same device that I started it.