Missing period (16dpo), high temps, BFN, WTF??? (An indulgent rant)

[MrsHappy]

I am having a strange and annoying cycle and I wonder if anyone has had the same...

I chart my temps so have a good idea of when I ovulate and this cycle my temp rose on 7 October. I should have got my period on Monday (14dpo) but my temps have stayed above the cover line (alternating between lower temps and higher ones, but still above that line). I had a pinkish wipe or two on Sunday and Monday and so thought my period was coming but so far: nothing. I had period-type cramps on Monday and since then have had occasional backache but nothing to get excited about. I don't feel pregnant, if that means anything (and normally I can tell that something is going on).
Last night I did 2 HPTs (ones that claim to detect 10 whatever-they-ares of HCG) and both were negative.

Does anyone have any idea what this is?

My options are, I guess, ovarian cyst, pregnancy (unlikely) and ectopic (worrying, as I have already had 2 this year and had a salpingectomy last month).

Has anyone had a similar experience and what did it turn out to be?

Oh and also (whiny voice) why can't ttc be straighforward???

[MrsHappy]

Look at that. I write the post and promptly find my period again. Must be the magic of Mumsnet...

[Issy42]

Sorry to hear that MrsHappy. Hope it works for you next time.