can't get pregnant

okay so I haven't been trying to get pregnant but when I was 18-19 I had unprotected sex with my boyfriend and I didn't get pregnant and like we kept doing it and still nothing. then after that I was maybe 21ish my same boyfriend when we was having sex the condom broke and I still didn't get pregnant. and with that same boyfriend I had sex with him like 3xs a day for a week unprotected and still no pregnancy and now that we are actually trying I'm 24 now still I won't get pregnant.