Does sound like you just pulled a whitey and had a bad trip.
I dont think you just snap into Schizophrenia just like that, it comes on over time and gradually gets worse.
Ive had the same experiance as you years ago when i used to smoke weed pretty heavy, i'd say if you have the same haalucinations while your not stoned then that'd be something to worry about.
I used to smoke around a quarter of skunk or upto an ounce of resin a day, i smoked it religiously each day since i was about 13-17.
I cant help but think that the weed really messed with my head and caused my illness, i stopped smoking it because it got to the point that i just cudnt stand the hallucinations anymore and they were happening when i wasnt even stoned.
You seem sensible, stop smoking it.
Drink beer, that doesnt mess with your head as much.