Hi seastes! I totally agree with Bernard. It sounds like seizure activity, and there are lots of us here who have perfectly normal EEG's.

Honestly, no test is 100%. They help, but only if you're seizing during the test. *shrug* Your daughter will most likelly be diagnosed, as she has had more then one episode. That's how they usually diagnose it. If there's no history of epilepsy in the family (and migraines count as aform of epilepsy), they will most likely tell you that she has "ideopathic seizure disorder". That's the fancy way of saying, she has seizures but we don't know why.
Here's some info the doctor will want:
1. medical history (for example, did she have any head injuries or high fevers that lasted for a long time as a child.)
2. family medical history ( Are there any people in the family with seizures? And don't be surprised if there are, but they never wanted to talk about it....oh, and anybody in the family with diabetes?)
Also, If I were you, I'd have your daughter jot down the following info in a journal, and keep track of it from now on.;
1. food and drink (when and what she consumes, and how much)
2. sleep (how many hours uninterrupted does she get each night?)
3. stress (any new stress? And what does she do to deal with her stress?)
4. odd feelings (odd smells/tastes/sounds/feelings, migraines, fuzzy or spacy feeling...)
5. seizures (when they happen, how long they last, what she was doing prior..., and where.)
6. Her time of the month. (When did it start?How long are her cycles.)
Here's why she wants to keep the journal. To see if she can figure out what is triggering her seizures. The most common triggers include too little sleep, too much stress, and too many stimulants (coffee,tea, energy drinks, sodas, etc. ).
If she can figure out what's triggering her seizures, maybe by dealing with her triggers, she can get control of her seizures. Other triggers are hormone fluctuations, food allergies, low blood sugar , flickering lights and patterns, etc....
While you wait for the appt, try to get her on a consistent sleep schedule (7 hrs every night...), cut back or out the caffeine, get her on a regular eating schedule, and try to make sure that everything that she eats is healthy. (NO diet foods or sugar free foods...artificial sweeteners can trigger seizures too.)
I hope this helped. Feel free to ask questions, vent in the padded room, or chime in.

You arent the only one who has gone through this, and you're not alone.
And if your daughter is diagnosed, dont get depressed. It's not the end of the world. Think of it like diabetes or asthma...a medical condition to be dealt with.

Many of us here drive, have advanced degrees, have careers, loving families, etc.... this will only be as limiting as your family makes it..

Take care!