First question would be, do you in fact have OCD? It is a very much overdiagnosed condition and if often confused with obsessive thinking alone, which is common to everyone with mental disorders as well as many without them. It only matters because the next question is, are you in therapy? The treatments for OCD would eventually involve not doing the compulsive behaviors it entails and hopefully with repetition realizing nothing awful will happen, whereas the therapy for obsessive thoughts is somewhat different. But taking a drug doesn't eliminate trying to see if a therapist who specializes in anxiety treatment might be able to help you. There's no guarantee therapy will work, but if it does, great. The last thought is that the Zoloft isn't working very well if you're still having this much anxiety about things.
Yes, more of the pure-o OCD without the compulsions and yes I am in therapy. My first fear used to be that I was becoming a murderer because I would have violent intrusive thoughts. And then studying mental illness in my class created the fear that I'll develop schizophrenia. The Zoloft has worked and shown improvement but now with these illusions I'm scared I'm developing schizophrenia. Do you know if that's an early sign of schizophrenia?
I'm no expert, but you're born with that disease, it doesn't "develop." It does, however, manifest itself at different ages. When you have it, though, you usually don't know it -- it's a psychosis -- and I don't think you have it. I think you're just suffering from anxiety, and finding out if there's a why or, if not, learning how to think differently is the answer if there is one. Good luck.