help please

Baby • Sun, May 14

According to Glo my period was supposed to start 3 days ago. So I'm 3 days late. The last time I had sex was April 21st and we used a condom and he did ejaculate will he was in me with the condom. And he was 100% sure it didn't leak or rip. And I've been gassy and constipated lately. Why is this