HPT not showing positive ?

I am currently on CD 37 & 18dpo. Last menstrual on March 18th. I usually have a 29-31 day cycle with like 4-5 days of bleeding. This has been by far the weirdest cycle ever. I'm very late and all BFN hpt's. My breast are sore, and my bbt has stayed up. I've read where a women's HCG levels are so low that a pregnancy can't be detected in the urine, and some find out at like 8 weeks etc. I haven't been on medication nor have I done anything different this month. Ugh. All I want is clarity. If I am great if not can AF show up so I can try again.....😞😡