Past TWW, bfn and no AF

I'm TWW ended last week. Bfn 15 days after iui. I keep thinking I'm going to get my period- woke up yesterday morning with extreme cramps but nothing. I think I might retest in the morning but not keep my hopes up. AF was due Friday (but it does vary) so my doctor won't see me until BFP or 1 week late.... It's driving me crazy that AF hasn't shown up yet. It this is a true bfn, I'm taking June off. I'm so drained.