I have had it happen to me in the 80's.
I was able to isolate it down to one batch of old weed that had mold on it.
small little white dots (not THC).
after that I carefully inspected anything I consumed even manufacturing myself at one point instead of using commercial, you can smell mold and it is visible when pods reach large enough sizes, many toxic even in visibly undetectable amounts when consumed through inhalation.
my experience was more of a white out than a black out, sunlight coming through a window kept getting brighter and brighter till everything in the room got grainy like a bad b/w camcorder then I fell over (was sitting down) and started twitching on the floor (in my mind trip I was stuck in a back alley fighting some hooligans) so that might explain the twitching of outer limbs, then again it could have been seizure like reaction to the mold other people smoked about the same amount of the moldy weed on numerous occasions and nothing happened to them so it may be a unique allergic reaction or a combination of my own body chemistry at the time (dehydrated/adolescent/ etc etc).
Some molds are deadly when consumed, look at Britney Murphy case, so it is something to consider for anyone who smokes remember Ergot is a mold and one from which LSD derives and Tricothecenes has been used as a war agent so there is no telling what different molds are going to do to the body when consumed or inhaled through burning but there is a heck of a lot of toxicology reports already drawn up for molds and their effects when consumed orally or inhaled without burning to look at for ideas of their effects to the body.