I couldn't pick just one, and I don't know which ONE thing caused my first seizures.
I had a seizure cluster in January of this year. I had three tonic-clonic seizures, two in my bed and one at the hospital.
I hadn't eaten anything that day, my daughter was sick with the stomach flu. I was planning on eating after she went to bed, and instead had a seizure. I was actually hungry, and planning my food (the oven may have even been on). I was also dehydrated, though I had been drinking through out the day, it wasn't enough.
At the hospital it was found that my potassium was low, along with the dehydration.
Also, everyone has said "It's stress" and I want to smack them all. Yes, I was stressed out that day. But I have been in far more stressful situations before and since then with no seizures.
However, in looking back over the years, I believe that I used to have absence seizures as a kid. I remember frequently staring off into space at school, or at home. But only for a few seconds at most. I could never bring myself out of them when I noticed them, but after a bit it would "stop" and I could blink or move my head. I remember things would get a little quiet, muffled sounding. I always thought it was normal, something everyone did. But it was more than just staring off and not paying attention because I couldn't make it stop like I could when my mind just wandered.