I agree with drifter. You may have some kind of schizophrenic disorder. I would see a therapist who can diagnose mental illnesses. I think it would help to get in a habit of writing down your feelings often. That would take the pressure off of you and there would be less to talk to yourself about. Write down all your worries and fears and bring that with you to therapy. It might help you express yourself more and give them some idea what is wrong with you.
I used to talk to myself alot, it was often about the same issues you talk about, and I still do occasionally but the medication I take really stops all that almost entirely. If I forget my meds or I neglect to take them then talking to myself is one of my first signs I am relapsing.
I think you will be okay if you see a therapist right away. They need to assess you and get a clear history of you, if you can bring a family member for support -to be with you and talk to the therapist- that will make it easier for the therapist to assess you.
Also, meditations on youtube for calming the mind might help too. I find if I do them in the morning when its quiet I have a much more productive day.
I wish you good luck and congratulations on having the courage to speak out about this.
you may have paranoid schizophrenia I suffer from SZ since '07 dxed same type youll need meds and support groups meet others with mental health programs look around becuz you are not alone take a chance with meds and post your progress here in medhelp