Dumb question

So on the 13th, my husband and I had a quickie, like under 5 minutes (I came and he did not). My period was supposed to start that Friday and I still haven’t. I’ve taken about 4 tests and they all are negative. A few years ago my period was extremely late to the point I had to go get a pill in order to “restart” my cycle.

What are the chances of actually getting pregnant right before my expected period?

This is from this morning.