I had a very vivid dream the night before my ultrasound. It was my 3rd child, first ultrasound, and I really wanted a girl as I already had 2 boys. During my dream, I was having one of those newer 3D or 4D ultrasounds. I saw the baby's face and fell in love. The feeling of love was so strong and so overpowering! In the dream the nurse said, "It's a boy!" I didn't care because I was so in love. I then woke up. That afternoon I wasn't surprised to hear the technition tell me that I was having my 3rd boy. The feelings of love, leftover from my dream, covered up most of my disappointment. I feel like it was God giving me advanced warning and an extra measure of love for my now 3yods.
Maybe God was letting you know how your son feels so that you can better comfort him and reassure him during his seizures.