Should my SOP be a narrative of all the events in my life that lead me to develop my research interest?
To answer your top-level question:
Absolutely not.
Your statement of purpose should be an account of what you want to do in graduate school, and your qualifications to undertake that research. Admissions officers do not want to read about everything you've done as a researcher since you were a child. Nor do we want a blow-by-blow account of your research career.
Instead, briefly summarize your history, and move on from there. The bulk of your essay should be what you plan to do, not what you've already done.