I don't know if cannabis causes schizophrenia but I got it bad after a trip to Amsterdam. My take on Schiz is that is basically an over active imagination that gets out of control.
I don't really do weed much but when I do I don't really get any of the schiz effects as I've trained my brain to give a shrug to any negative thoughts and remind myself that every little things gonna be alright.
If you have schiz or are worried about it then my only advice would be to take it easy. If you get hallucinations then make sure you know they are hallucinations as then they are just a product of the mind and humans have a great knack at being able to alter reality but not always consciously and directed towards a happy outcome.
I often hear music coming out of my speakers when my hifi is turned off. I've got pretty good at changing the station just by directing my mind onto a different wavelength.
Not everyone who has schiz is troubled by it and I learned a great deal from watching many videos of Richard Bandler. Some say he's a genius and others say he's a conman but he tells a very good story. He's amazingly charismatic and good humoured. A lot of his stories gave me belly laughs. He talks a lot about schiz. There is a story in one of his books about a schiz called Andy. Andy has people coming out of the television screaming and chasing him. It freaked him out. Bandler asked what he watches and he said Little House on the Prairie. So Bandler explains about Mary, I believe, who he doesn't much care for and I think calls her a snippy bitch. So he says to Andy... you know what? You have a million dollar condition there... tell me how you do it. Andy was a bit perplexed and asked what he meant ... Bandler goes "have you ever heard of the playboy channel?" And with that single sentence he was thinking in a completely new way.
The thing is you're not mad. Your just letting your creativity get the better of you. Get a hold of the reigns and go for the ride of your life.