2IUI - no period but BFN?!

Amanda • Proud Mother and Wife to my little family
Hi,
We had our second <a href="https://glowing.com/glow-fertility-program">IUI</a> August 18th (so I know for a fact that's when I ovulated).
Doctor said to expect my period today - September 1st and the 2nd I would officially "be late"
Well, no period, not even spotting. No cramps...but I took a cheapo pregnancy test and it came back BFN.
I don't want to get my hopes up, and if still nothing by my official "late day" I'll call the doctor for sure...but... Any success stories like this??