5 days late and negative pregnancy test

Aja

Wanted to reach out and see if any other women have dealt with this. Long story short, I only had sex the first day of my ovulation window and 4 days after earlier this month. My periods come like clockwork I’ve never had a missed or late one before outside of pregnancy. My breast have been a little sore and I’m slightly nauseated which is on par for what my last pregnancy was like when I found out I was pregnant around the 4-5 week time frame. So I’m just terribly confused on why my cycle hasn’t started and I have a negative test. I haven’t changed my lifestyle lately so I know it couldn’t be that. I just want to see if there anyone else who had some insight. I have a doctors appointment to get blood work done soon.