Yes, it can be a part of the disease. There will be a very distorted self-perception and is connected to the disease especially if you suffer from the fear
of rejection. Schizoaffective disorder is a very complex and difficult disease to treat, even with medication, which I presume you are on. All psychotropic medicines have side-effects: that is inescapable. But I suspect that you are depending entirely on medication when in reality you need to combine it with counseling or therapy. In therapy you will learn a lot of coping mechanisms and techniques to remain functional and lead a close-to-normal life. You will also learn about emotions and how they can impact your condition adversely. Expressing emotions in an appropriate manner will equip you for life. Talking and sharing about the many disturbing thoughts and learning to understand yourself and moderate your responses will go a long way towards normalizing and training your mind. Exercise must be a regular part of your life for various reasons. Put yourself on a productive and strict schedule. The idle mind is the devil's workshop for sure, and more so for a schizoid.