Please help...

Me and my boyfriend have been trying to get pregnant for months.. we try every time I ovulate and he will finish in me everyday of my ovulation.. my period will be about a week late sometimes even two and I start bleeding really heavily after that. Just last month we thought I was pregnant I missed my period the whole month only had light spotting (which is normal for my family! every female had spotting there entire pregnancy) then the next month my period came right on time.. what’s going on?