I still think that it is possible that these thoughts are OCD-related. My brother has a similar problem; he pictures himself killing our parents, and then he feels incredibly guilty for having those thoughts and wonders whether he would actually carry them out. The thoughts are incredibly vivid; he can see the blood and everything. He has OCD. No one has even suggested psychosis.

Psychotic symptoms include hallucinations and delusions. These thoughts don't sound like either to me. They aren't hallucinations because they are your thoughts; hallucinations generally are external. They aren't delusions because you don't have a firm belief that they are true. I know that such intrusive thoughts are scary, and I send you all the warmth and comfort in the world. But I really don't think that these thoughts make you psychotic.

I am more worried about the paranoia you experience while driving. That could be psychotic. How strong is your belief that the cars are following you? Is it something that seems 100% real at the time, or do you question it as you experience it?

Also, do you have a diagnosis of OCD?