Why havent i Got Pregnat yet at ALLL.....?

Okay ive been On BirthControl for 2 years now and me and my First Boyfriend had sex and stuff and un protected alot and he says he pulled out and im like okay and the kondom broke and we had sex alot and i wasnt planning on gettin pregnat but my mom said that she had alot of miscarriges and so my next Boyfriend/A.K.A Fiancee had sex and the kondom broke and he had Unprotected sex to and still i havnt got pregnat im scared that Im Not able to have kids and i really want to least 2 to 4 kids and ive been told Birthkontrol Only like 75% Effective but sometimes it 0% Effective and im so scared i aknt have kids and my Boyfriend/A.K.A. Fiancee wants kids so bad and ill feel so bad that i kant do that for him But idk yet.....im so scared.....i have had signs of Pregnacy but nothin indicating im For sure pregnat but right now it might be 50/50 but the signe went down and idk but my Fiancee said he Gonna get me a Pregnacy test But i Doubt anything is gonnna happen i mean i dont want to be pregnat but i would like to know if I Kan get pregnat PERIOD.......