Late period

So I just realized that I’m almost 6 days late, but I haven’t had sex in at least a month and we used protection and I’ve had absolutely no signs of pregnancy but I haven’t taken a test yet. I’m freaking out a little so any advice would help. I’ve changed up my schedule a lot recently and I’m working a lot more could the stress and more activity have something to do with it? And I got really sick on the day I was supposed to start very dizzy and horrible sore throat. Could that also be setting it back?