**READ** help! BC and not getting period

So I was on one BC and it never gave me my period and the doctor said it was fine but I switched BC's and this new one gave me my period for the first 3 months or so. This month I took the sugar pills and no period. My cousin took this BC too and said after 3 months it just took her period away completely. Should I be freaking out? My bf never came inside me either.