Jean,
I have had similar "spells"/seizures,, total of 9 in last 4 yrs.. and NEVER before that,,, in fact the first one I had was what led me to an MRI and diagnosis of AN.. so I had this for about 3 yrs before my surgery which was last Oct.
ALL of my Drs. deny that they are related,, I am not so sure,, I recently turned 60 ,, YUK,, and had worked for 30 yrs before retiring 3 yrs ago. I had never had any type of seizures prior,,,,
I do about the same thing as you describe,, dizziness,, aura type feeling, hard to explain that one, nausea, sweating , overall faint feeling. The first time I did go to ER and nothing was discovered,, vitals were all ok, after seeing neurologist, he said hospital was not necessary , if I come out of them ok which I do. They are very scary and extremely exhausting to the entire body,, I might agree with you about the hydration factor. The last one I had I had been at the hospital with relative all day and had not eaten or really had any water etc, and that night about 7:30 I had one sitting in the back yard with my husband,, he really hates these spells by the way!! But no more than I!!
I hope after seeing a neurologist you can determine a cause although I do not have one after 4 yrs, seizure meds, 9 seizures, and tumor removal....... very frustrating,, especially after being fairly healthy all these years..I have not had any other change in health that would even remotely impact this type of behavior.......... even after substatial debate with neurologist about my belief they may be related somehow,, he states that ANs affect a different part of the brain than seizures "generally" happen in,, even though mine was pressing on brain stem also..... soooooo there ya go...
They are very scary to say the least,, I empathize with you and hope that is the last one you have.. I do drink occasionally, however, since surgery , I can not tolerate more than one at a time and that is not often.. seems to give me too much "wonky headedness",,, and Lord knows I don't need any more help in that category!! Sorry to ramble, but wanted you to know my story and that yes,, these things can happen even in someone with AN,, but "supposedly" they are not related,, and that is quite frustrating................good luck and keep us updated please,, Jane