BFN? What the heck?!

Meredith
Calendar says 12 DPO, elevated BBT for the past 12 days (normally runs in the low 97s and has been 97.98 and higher I know I ovulated because my temp hit 98.9 June 9th right after a major dip), spotting for two hours 3 days ago. AF due Thursday. Tested today FMU and got a BFN. What's the deal? Wait until missed AF?