There’s still no 2nd line appearing on my test strip and I’m literally a few days from ovu date!!! How come?

I had presumed something would show by now!! We had sex sun morn and wanted to hold off till wed giving several days for stronger sperm, but wed is the day before ovu, too late I thought!!

Sure I’ve read we need to a few days before ovu date!?

I’m a year in and a few weeks off 40 hence starting to use strips as a final help!!