Overdrive

I've been prescribed Seroquel (used primarily to treat Schizophrenia). But I am confused! I suffer major depression and anxiety, and have done so for several years. However, I have all the classic negative symptoms of SZ, and, while I am currently not experiencing any of the positive symptoms, I have had 2 episodes (1998 & 2000, the latter lasting 8-10 months), where I saw a particular 'being' that followed me everywhere I went, and this being spoke to me frequently (in a way that terrified me). In 2000, I became a recluse, lost interest in everything, and became paranoid that everyone hated me, and that I was a failure. In one incident, I slit my wrists believing that the being was telling me to do so. There are several incidents in 2000 where my wife tells me I did certain wierd things in her presence, yet I have no recollection of these things. I would stare blankly for hours, scribbling words that had no meaning. I hated the dark, believing that if I got up the being would 'get me'. In both 1998 and 2000, I experienced incidents where I was convinced another person was in the room with me, and this inspired paranoid terror in me. I remember jumping into bed, and, within moments, believing that I was being pushed down by another force other than my own, and, the more I tried to get up, the more I was pushed down. At one point in 1998, I stopped breathing (so I believe?) for a minute or so. I remember lying in bed shaking, curled up like a ball, sweating profusely, afraid of getting up to switch off the light - because the 'little hooded man' was always standing right where the switch was. I remain convinced that what I saw and heard in 1998 and 2000 was very real (others say I am crazy, so I no longer talk about it). Thankfully, I haven't seen the being for about 2 years now, although I am often thinking someone is around me (I just can't see it clearly like I used to). I was okay in 2001 and most of 2002, although I was depressed. In late 2002, I went to a psychologist for the first time, who referred me to a psychiatrist at the end of 2002. She prescribed the Seroquel, but didn't tell me her diagnosis (?). I am currently avoiding any contact with friends, and feel listless, unmotivated and agitated. I am not interested in things that used to appeal to me, and I frequently lose my temper. I don't know who I am anymore. I am certainly not the same person I was four years ago. I sleep a lot. I think deep thoughts, mostly negative. I spend hours staring blankly into space, thinking about nothing in particular. I think I hear voices sometimes, and I am always looking over my back, believing someone to be following me. I was convinced, recently, that a police car driving behind me was purposefully following ME (although I realised - albeit the next day only that that was not the case). Please tell me if it is possible that I had a schizophrenic episode in 2000, and if it is possible that I am SZ. Oh, and I have never doubted that I saw this being and that he spoke to me. I could even draw a picture of him! (My wife, who was most times with me, saw and heard nothing)