Мой and моя are possessive pronouns, like "my " in English.
When we choose the gender (мой - masculine, моя - feminine) we don't consider the gender of the possessor, the person to who something belongs. We consider the GRAMMATICAL gender of the word denoting the possessed object. You can tell the grammatical gender by the ending of a word. Here's a webpage explaining how to define the grammatical gender of a word.
http://www.russianlessons.net/grammar/nouns_gender.php
Examples:
Мой телефон - both male or female can say that. The word телефон has a consonant in the end, so grammatically it's masculine and we must use "мой".
Моя книга - can be said by a man or just as well a woman. Книга has the vowel "a" in the end, grammatically it's feminine, so we use "моя".
If we talk about relations between people, we also use мой, моя and the "possessed thing" is in fact not a thing, but a person in relation to you. In this case, the grammatical gender matches the biological gender of that person. Again, it doesn't matter if the person who uses the word "my" is a woman or a man. Both a son or a daughter can say "мой отец" (отец is masculine) or "моя мама" (мама is feminine).
МЕНЯ is not a possessive pronoun. It is the genitive and also the accusative form of the word "I". In simple words, it's very much similar to the English word "me". People sometimes get confused, because we use "меня" to express the idea of possession:
У меня есть дом . - I have a house.
But in this case, we are not saying "my house". We say, literally, "there's a house with me". Sounds odd in English, but this is a way to express this idea in Russian.