Cycle day 46 - BFN

So my cycles are usually between 28-31 days and hardly EVER late but I am on CD 46 today. We have been TTC for 8 months. I took 2 early HPT on CD 24 and CD 28. Then I took 2 more on CD 44, and all have been BFN. No faint lines or even evap lines. Any ideas? Has anyone gotten a BFN this late and really been pregnant? If I did conceive I would be 6ish weeks along and should definitely be getting a BFP, right?