If this helps, I once, and only once blacked out from smoking weed.

I smoked 2 joints one night, went to the washroom, came out, and my hearing went all, fuzzy sounding, lost the ability in my legs and I bashed my head on the floor. I couldn't move, or see anything for bout 2min.

My guess again, you were just really, really high. Try smoking a little less next time and see if it doesn't happen again