Sir..I Was Married Recently.I Am 23 Years Old .with Out

Sir..I was married recently.I am 23 years old .with out parents concern I got married my girlfriend.now we want to go for inter course without condom.but we don't want to have children now..so what kind of tablets do I suggest to my wife ? Her date was yet to come on this November 30.what are the safe days to go for inter course without condom?