some psychotic tendencies, Possible schizophrenia?

I have chronic depression, generalised anxiety disorder, OCD, and some psychotic tendencies (according to my doctor and the several psychiatrists I've seen). I'm being treated with lexapro for the depression and anxiety, as well as olanzapine for my psychotic symptoms and as a general mood stabiliser (5mg daily). I had a mental breakdown when I was 19 due to drug abuse, and a severe depressive episode when I was 21 due to alcohol use.

Recently, I tried to come off the olanzapine, an attempt that was sanctioned by my doctor. I got down from 10mg daily to 2.5mg in the space of three months, before my psychotic symptoms returned. These involve the perception of faces in inanimate surfaces (although I don't actually see them, I just get the impression I do) and the occasional irrational thought (my food being poisoned, even though I know this is certainly not true).

Now, I have always had a fear of developing schizophrenia. It is true that I am experiencing many of the negative symptoms attributed to the illness: general apathy, inability to express joy, anhedonia, extreme social withdrawal etc. But I do not hear voices, I don't think I'm the messiah or the devil, I don't feel insects crawling underneath my skin etc. I do have what are termed "intrusive thoughts", which is characteristic of OCD.

I'm due to see a psychiatrist within the next few weeks to make an official diagnosis, but my doctor who referred me did not think I had schizophrenia. Neither did the one I saw before, or any of the psychiatrists I've seen previously.

Nontheless, in your opinion, should I be concerned about having schizophrenia? I'm not going to lie, that could really finish me off. It's been damn hard getting this far, and I'm not sure I could handle such a diagnosis.