AF 13 days late but all BFNs

Stupid freakin stupid cycle. UGH. I've never been more than a day late...always had 29-30 days cycles with the occasional 31 day deal, all 11 years of having periods. And I'm on cycle day 43 today/13 days late but getting nothing but BFNs. It's very upsetting and no one will examine me without a positive test. I had a blood test done last week (when AF was a week late) and it was negative.