Yo bro. Firstly, you need to chill out!
Unless she tooksome god awful insane amount and went into coronary, she's gonna be absolutely fine. I know its a bit of a shock when you love someone and you witness them having a ruff time on a substance you know little about, but just be cool.
If you are waiting on her every need, showering her with advice, and especially repeating the worst question possible "are you ok?' all the time, then despite your good intentions you are only going to worsen the situation.
When you are in a state of insecurity and fear due to the shock and unfamiliarity of a particular substance, what you most need is someone to act entirely nonchalant about your symptoms, and to wave them aside with an indulagent smile, whilst stating that this is completely normal, it will pass, its just a comedown, and you will look back on this and laugh.
Distract them from their symptoms don't acknowledge them, cause the LAST thing she wants to think about right now is "AM i ok?", and too much fussing will spook her into thinking their is a problem.
What she needs to do is curl up in a warm bed, with a hot flask of camomile tea, a vastly uneccesary amount of cushions, listen to Bob Marley, dim the lights, watch the most sickeningly fluffy disney movies you can think of, and if you can find a valium or sleeping pill or get her to have a couple of glasses of wine (but not all three!) thats all the better, massage and orgasm is fantastic, eat hot veggie soups and sleep. It can actually be quite enjoyeable!
Think about it mate, if anyone gets over tired through lack of sleep, they get chilly, tetchy, exhausted and run down for a couple of days. It will pass.
In 1995 in Rotterdam Holland, I was Djing at a 9 day rave in a squat. I played every day, dance almost the entire time, ate almost nothing except for soup and amphetamines and didnt sleep a single wink for the ENTIRE 9 days and into the tenth night.
I'm not proud of it.
I'm just trying to say, one night on the whizz, haha, she's just experiencing her first comedown bless her,and really, she's just a bit chilly moody and sleepy, thats all mate.
No biggie!!
Trust me on this. I am an older fella with a wife and family, a DJ , and record label owner. I grew up in the U.K from the birth of the rave scene 21 years ago, and have been and seen in some extreeeeemely messy situations. What she's experiencing may be scary to her, and your obviously a bit freaked, but so was I the first time I fell off my bmx and grazed my knee.
Peace DJ