Some posters have said that they have not felt well enough to go to work but then well enough to go out later.
I have to be really really rough to not go to work, no recovering from that in a few hours! If I feel a bit crap and have work during the day and a night out, I realise I will probably manage one or the other so I go to work and rest in the evening.
I think that's where the logic lies for the OP, in that her dd should only be missing school if she is really poorly. If it's something a bit of rest could cure, no reason not to go to school and then rest at the weekend/in the evening.
Otherwise the message is, if you have a night out planned and you feel a bit poorly, rest during school time so you can still go out.
That's the life lesson, you have to prioritise and usually that means work (or in this case school) and not pleasure. Unless you have limitless cash and no need to keep a job.
But yes OP, it wouldn't really have mattered one way or the other, this decision will not haunt her for the rest of her life
You made a judgement call, she was aware in advance of how the day would pan out, it's fine, don't worry about it.