6 days late & BFN!!!?

If you ovulated on CD24 then you are only 11DPO which in most cases it is too early to test. Wait until 18DPO(CD43) and test again. If AF still no show and test still neg. go get a blood test.

If you ovulated on CD24 and your now on CD35, that would put you at only 11DPO . How long is your luteal phase? You are only late if its shorter than 11 days. Its the time between your ovulation day and period that determines if you are late . Not your all around cycle length. Its reasonable that you didnt get a positive yet being only 11dpo. My advice would be to wait 3 more days. That would put you at 14 dpo and you would be more likely to get a positive result.

You also dont need a big thermal shift to determine ovulation. Your chart determines ovulation based on when your temperature rises above what it was it before and stays higher for 3 days at least. The difference in a thermal shift that indicates ovulation has already occured can be as little as .5 degrees. I dont think your chart is wrong.

ADDED: I dont be mean to be rude but "always" having a certian cycle length means nothing. It is very common to have a cycle that is out-of-whack every once in awhile. Mine used to "always" be 32 days like clock-work and without any warning, they changed. Also a 5 day luteal phase (from day 24- day 29) is a fertility issue. A fertilized egg usualy takes 6-12 days to implant ( your in that time frame with no period so I doubt its that short). It would also have helped to tell people when you usualy ovulate. We are only here to give advice, and we can only give advice based on the info you provide.

If you OV around cd 24 then your cycle will be very long this month, AF will probably come around cd 38.