Considering you have epilepsy (assumption since you are posting here), my uneducated guess is that you are awake for this part of the seizure, but you get knocked out afterward.
My secondary generalized seizures have always caused me to sleep for several hours afterward. And the one I had where I was status epilepticus, I can remember being in severe pain, and feeling my arms and legs shaking. That was most likely the CP right before it though since you aren't supposed to remember anything about the generalized seizures - I remember shaking, hearing a screaming that I wished would stop but wouldn't, then being thrown head over heals down a long dark tunnel as pain traveled up my spine, at the end of the tunnel, I realized the the tunnel was spine, and my mouth opened, and I was flung out my mouth into a bright white light - thats when I realized the person screaming was me, and I saw three doctors torturing me and laughing about it. Then I entered a state where I was aware, but unable to think, or use any of my senses. It was very peaceful. Then nothing, until I "woke up" from the seizure. - apparently some time during this seizure I was actually punching and kicking the ER doctors but I've no memory at all of that. I imagine I was defending myself against their torturing me with that giant drill as big as a house that occured during my CP hallucination.
My worst seizures always end with me sleeping. They also are more likely to occur when I'm already asleep (aside from the ones triggered by things like stress and lights). If they've occurred while I'm awake, I'll often not remember them until someone jogs my memory, if I remember them at all. I can tell I've had ones at night because I sleep longer than normal, I wake up with my cat guarding my face, and I wake up in a foul mood.
A high fat diet has greatly reduced these (modified atkins for epilepsy) - when I don't have problems eating, it actually works better than the medicine does. I never eat soy as even a tiny bit can bring on a bad seizure for me. Also caffeine helps bring on seizures, and my doctor told me to reduce my salt intake because water retention increases electrolyte buildup. Also have you tried keeping a seizure journal? I use seizuretracker.com. Doing so, along with keeping an activity and diet log, can often allow you to identify seizure triggers you never would have thought of - I know that even though I don't get seizure headaches in my library, if I spend more than 30 minutes there, I'll have a bad seizure later on in the day. I never would have identified that trend without keeping the logs
