Do i have a mental disorder or just a mental illness?

If you truly had schizophrenia, you'd be the last person to know. Just because you know these voices are actually stemming from your cognitive self, proves that you're not schizophrenic. Your concern may be a manifestation of your anxiety. Oh, anti-psychotics won't work and the solid solution requires a change of lifestyle (diet + hobbies + exercise + socialization)