Without interviewing you in person I cannot offer a reliable diagnosis. You believe that you may have schizophrenia but the more likely possibility is obsessive compulsive disorder (OCD). A psychiatric evaluation would assist you with the proper diagnosis.
What you have described with regard to being paranoid is not the typical type of paranoia that an individual with schizophrenia experiences. Individuals with schizophrenia and related psychotic disorders who experience paranoia typically become preoccupied with fears such as the belief that others are following or watching them or that their thoughts are being extracted from their mind, etc.
To be diagnosed with schizophrenia, additional symptoms would need to be present including delusions, hallucinations, improper expression of emotion, poor social functioning and disorganized thinking, among others.
Schizophrenia is a thought disorder whereas OCD is an anxiety disorder. Your letter was written in a very logical manner which adds support to my assertion that schizophrenia is an unlikely diagnosis. In addition, your fears are health-specific which, in the absence of other schizophrenia symptoms, is more characteristic of OCD than schizophrenia.
My advice is to have a psychiatric evaluation for a mental health diagnosis. An evaluation could quickly rule out schizophrenia. With regard to anxiety disorders, delaying treatment is not recommended. The primary reason is because without treatment, anxiety disorders tend to become progressively worse over time. The most effective treatments for anxiety disorders include cognitive behavioral therapy, antidepressant and anti-anxiety medication and for OCD, exposure and response prevention therapy. I hope this answers your question. Please take care.