It's going to be worrying for you, but for now you're doing all you can.
I suspect Bella's behaviour will have to be monitored, and unless it takes a serious turn for the worse, there's not much more you can physically do. As Paula says, sometimes these can be a one off in the electrical wiring of the brain, as it were.
Our lovely old Tess suddenly developed fitting when she was around 5. In her case it was triggered by over-heating - she was a beardie collie cross, with a heavy double coat. We solved matters by keeping her clipped, and making sure so far as we could that she didn't get heat exhaustion (not easy with a dog who lived to run and play, but we managed).
It may have been the case with Bella too, if she was getting very excited.
Try not to worry. You and your daughter deserve to have a lovely weekend, and hoping everything settles down so you can have your trip together without fretting.
Keeping all crossed.