It is difficult to know what disorder, if any, you may have. It is true that having a family history of schizophrenia may make it more likely that you would develop the disorder. Yes, it slightly increases your chances, but it does not mean that you are destined to develop schizophrenia.
You may not have any one particular disorder. You may be suffering from a number of various symptoms but nothing that is diagnosable at this time. I would suggest meeting with a mental health professional for a diagnostic evaluation.
I find it encouraging that over time your social life and presumably your social skills have improved. You do, however, continue to feel depersonalization as well as paranoia and those symptoms are concerning.
You asked about whether your symptoms are prodromal symptoms, presumably a sign that schizophrenia is imminent. It is difficult to answer that question. You have had symptoms since the age of 14. That would be an abnormally long prodromal phase. It is possible that what you are experiencing are prodromal symptoms but I cannot tell based on a short letter. The typical age for the onset of a schizophrenia episode among males is approximately 18 years old.
Because it may be possible that you are experiencing prodromal symptoms, I would strongly encourage that you be evaluated and that you consider treatment. If you are in fact experiencing the prodromal symptoms of schizophrenia then being in treatment could help to prevent a psychotic episode. When it comes to psychosis or schizophrenia early treatment is very important. Research has shown that early intervention is associated with a more favorable response to treatment and better outcomes.
I think it is wise to be concerned. It is also important to be proactive with treatment, especially when it comes to psychosis or schizophrenia. As I mentioned above I do not know if you are experiencing prodromal symptoms, but if you are then it would be advantageous to be in treatment with a mental health professional. Delays in treatment have been associated with less favorable outcomes.
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