I thought the same thing, stroke, and it scared me real good. These episodes started when I was 23, and I'm 37 now, so hopefully that's inspiration enough to make you worry a little less about it.
I pretty much turn into a zombie, I can still function, as in drive, or carry on a conversation, but it's really hazy and sureal, like I'm on pain killers or something. they last anywhere from 5 minutes to an hour. After that, I'm still kinda out of it for a while.
Hope you feel better soon. Don't stress out over it. If the doc isn't too concerned, you shouldn't be either.