Help me Lady's??

Ingrid • Living life💕
My bf and I had sex when I was ovulating a few weeks ago. My period was supposed to be on Sunday but didn't it didn't show. Im very regular with it so I went on Glow and charted that it was late so the app backed it up and said I should get it tomorrow Tuesday.. I did take a pg test on Friday and it was negative.. Am I just late or might I really be pg??