This is so hard. I wish I could help you see that you can't be there all the time to monitor him (life doesn't work that way for any of us). For all you know, he could have just started the first seizure as you were walking in your door.

I am sending you all the strength I can muster, for the very best outcome of this situation. We've had a couple of cats who went blind, and they did fine after they adjusted, so if he stays that way, I bet he'll get used to it. Hope you can talk to your regular vet soon.