It was more of a thought experiment than anything, but I admire your choice.
As for nothing to relate it to, I was more meaning the way life felt to you. It is possible to live 1 day and feel good or bad, even without having anything to compare it to. Happiness can be produced by releasing endorphins (i think?) so a day of a constant release of them (i guess a bit like some sort of ecstacy trip) would make you feel happy, even if you weren't familiar with the term. At least I think so... perhaps... argh, curse you moon! :-)