My DD (10) has epilepsy, we have just got out of hospital due to seizures in fact.
She has focal seizures and presentation includes eye fluttering, eye scrunching, bursting into tears, hysterical laughter, 'losing her legs' (as you describe, they just won't work), head hitting, mouth curling, twitching, limb juddering (this is very subtle and happens when she is absent, keep a close eye out for this), stiffness, anger, violence, wandering...
She can be fully with it when having a seizure or she can appear to be daydreaming or experiencing a bolt of emotion eg. Laughing inappropriately.
My advice is to record anything you can, any odd behaviour. This is the most useful thing you can do right now. Keep a diary from today, write everything down. A neurologist will need details to know what type of epilepsy they may be dealing with.
With it being a weekend when you get back, I'd go to A&E. Don't panic but get her seen as soon as you can. Tiredness will lower a seizure threshold so if it is epilepsy (IF- ahgain, don't panic) travelling may increase any seizures.
It does sound like seizure activity to me but a video would be invaluable to any medical professional.
Keep us posted, OP. Hope she's ok.