What happened?

So I was out with my friend at subway. And we order our food and we get some water. Anyway. We’re finished eating and now I’m drinking some water.
He said something that made me laugh. And I choked a bit. But I got it down. However I still felt a lump in my throat. I said “wow that hurts.”
Then next thing you know I felt everything go away. Like my mental state was somewhere else completely.
I felt my body jerk a bit. But I made no noise.

I came back to him saying “hey, hey, you know what happened”
I look around still not sure of where I am yet entirely.
And then he proceeded to tell me I had possibly had a seizure. Or something of the like.

My vision was blurry for at least another hour.