Newly diagnosed and would love some feedback

Hello! My 5 1/2 yo daughter was diagnosed last week with a "seizure disorder." When I asked the neurologist whether it was epilepsy, she said, "not yet." I'm not sure where to go or whether I need a second opinion, but I'd love to hear your thoughts. The background: Libby had been having headaches all summer long and then had a grand mal seizure 5 weeks ago. Her CT scan, MRI, and EEG were all normal. She told me that as she was regaining consciousness that she could hear but couldn't see or move. I asked her if she had ever felt that way before and she said yes. She described one event to me that I actually remember - I was mad at her for not listening to me and she said that she actually couldn't see, so she had to wait a few minutes until she could see again before she do the task that I had asked her to do. She told the neurologist that she had also had 2 other episodes like that, but couldn't offer any details. She has definitely had a personality change over the summer - she goes through periods of being very, very quiet, maybe even detached, and seems extremely sad. She's normally a very loud, cheerful, bubbly little girl, so the change is very noticeable to everyone. I guess my biggest concern is that I'm a little surprised that the neurologist diagnosed her with a seizure disorder based on one grand mal seizure and only her recounting of other "episodes" and the behavioral changes. She was also diagnosed with unrelated migraines and that diagnosis I totally agree with. She has throbbing headaches centered around her right eye, finds sounds bothersome and wants to lie down with the headaches. We also have a strong family history of migraines. Couldn't the migraine pain account for the behavioral changes? Any thoughts??? Thanks, Steph