21 DPO, No AF, BFN

Hubby and I have been trying for about a year now with no luck. I've charted cycles for several years (bc of migraines originally) with an average 26-28 days with outliers of 24 and 30 very occasionally. I'm now 21 DPO on a 35 day cycle. I've not had this experience at all in the past four years of charting. I have NO symptoms of my period coming and NO symptoms of pregnancy.  I know when I ovulated based on CM and ovulation cramping. Two pregnancy tests later (one on cycle day 31/DPO 17 and the other in cycle day 35/DPO 21) and still negative. What should I expect now? I'd at least be a little more hopeful that this was a situation where I should just go for a blood test but have absolutely no symptoms either way...