My period is 14 days late as of today

I’m not too worried about this I just want to know if there is any possible reason why? There is no chance I’m pregnant, it’s been two months since the last time I had sex, and we used protection. I’m not stressed about anything, I’ve actually been less stressed then I normally would be these past few months. My periods are normally really regular. It’s been almost exactly 29 day cycles, 4 day long periods since the beginning of this year, but last month I was three days late and only bled for two days, and it was super light and painless which is really abnormal for me. Is there any other reason I could have missed this period? I’m not on bc or anything so I’m just really confused.