Two weeks after IUI !

I had an <a href="https://glowing.com/glow-fertility-program">iui</a> 2 weeks ago on day 10! My Dr said to test with home pregnancy test two weeks after <a href="https://glowing.com/glow-fertility-program">iui</a> and I did! It was negative :( but my period is not due till Tuesday (6 days from now) Could the test be wrong! Was it early to test today! I'm so sad and don't know what to do!! Should I stop using progesterone?
Anyone had the same experience? 
Thank you