I'm not proud of it but I used to be on opiate pain & I'd drink caffeine all day, it used to send me crazy & I'd have done something mad like that.
I also have rapid cycling bipolar. From her behaviour lately I'd say something is going on in her head!
I do think kids are kids once,let them have fun, but on the bathroom floor?! As someone has mentioned, the weight for the ceiling below. Then whatever you say, it's a bathroom, full of goodness knows what germs.
Surely it could have waited until morning and just pile a load up outside for them to jump in!