Where is my period?!?!

I'm 8 days late and there is absolutely no trace of any blood. 😒 the day I was supposed to get my period I had mild cramps for a few hours but my period never came. 5 days after my period was supposed to come the cramps came back and I had a really bad headache and my nipples were becoming sore. Now on the 8th day still no period, back pain, sore nipples, low sex drive, increased hunger, so I took a pregnancy test just now and it is literally as negative as a pregnancy test can be. I'm really confused. I stopped taking birth control back in April of this year and by the end of May I had a period and it was normal, then my June period was normal and now my July period is all out of wack. My fiancé comes inside me every time we have sex so I don't understand how I'm not pregnant yet. We've been having unprotected sex ever since I got off my birth control. I have been stressed but I'm honestly stressed 24/7 and it's never delayed a period before. I have a doctors appointment 8/11 with my gyno to do blood work and an ultrasound to make sure I don't have PCOS. 😔