Am I a Native Speaker of English?

The difficulty is that the question is not correct, unless you can define what the person asking means by ‘native speaker of English’. If you were born and raised speaking English as your first language, then certainly yes. If you learned English later in life, then perhaps not. If you were raised bilingually, then perhaps yes, depending on how much of your communication was in English. If you were raised speaking another language but spent your entire formal education studying through English, then also perhaps yes. You see that the problem is one of the question and the criteria. There are no internationally or globally agreed and recognised criteria of what a native speaker is.