A week late today

So my super regular af still has not shown up. No cramps, no break outs, nada!! Sounds like good news right? Well you'd think. Took a pregnancy test at 2 days late...BFN! Went in for a blood test at 3 days late...BFN! They told me to test again on Monday if af still is not here. Wtf this has never happened to me! I mean if I'm not pregnant the least my body could do is stay regular. I feel like my body has betrayed me!