I really recommend talking to your daughter's gp and asking for a referral to a neurologist. The gp may be thinking along the lines of a psychiatrist, which she may wish to talk to as well, but the neurologist will most likely ask for tests such as an eeg. It is possible to have a normal eeg and still have epilepsy, but it is also possible for the eeg to pick up some seizure activity.
To me, the symptoms you've described sound very much like simple partial seizures. I get these often, and for me they include shaky vision, dizziness, strong feelings of detachment, sometimes deja vu, odd feelings in my tummy, and they are almost always followed by a nasty headache and extreme fatigue. My epilepsy was diagnosed after I had a grand mal seizure, was referred to a neurologist, and two separate eegs showed temporal lobe epileptic waves.
Temporal lobe epilepsy has a variety of very strange symptoms. Odd sensations is the easiest way to describe it - sensations of sight, sound, taste, smell.. Feelings of detachment, odd feelings in the tummy, senses of deja vu, feelings of doom, anxiety, or even sometimes unexplained euphoria. Its just very different person to person. But because its so varied and odd, it can also look like a lot of different psychiatric disorders to a non-specialist. In fact, I was treated for anxiety before my grand mal a couple of times.
Your daughter is very lucky that you are so concerned for her though. If she is having small seizures, it is entirely possible for them to lead right into a generalized seizure any time. This means she could lose consciousness, which can be very dangerous at the wrong time. Depending on where you live, it could also mean no driver's license for her (which, at 17, could be the biggest tragedy to happen for her

)
i hope you two find out what is happening soon and that she begins to feel better!
-em