It appears that my period has arrived. It was just very heavy spotting yesterday, but I woke up to a saturated maxi pad this morning. There is still a bizarre lack of cramps, but there is enough red stuff that it looks like its safe to call this cycle over. We'll still confirm with the blood test tomorrow morning, of course.
I should also note for future refference that the constipation ended when the brown spotting showed up on Tuesday. I don't think this is a coincidence. I think I have enough data now to propose that constipation is good, and lack of constipation is a bad sign.
The question psychohist asked was about spotting last time around. The way I remember it there was a small amount of red spotting the morning of the day I tested, but I'd been having faint cramps for several days. Then I got my period for sure a few hours after we got the bad news. He though there was perhaps more spotting. Mostly I just remember cramps and a headache that would not die. I've been headachy this time around to, but it wasn't as bad.
I think the big difference this time around was I got actual implantation cramps a seven days post retrieval. Now that we know the blood tests I'm pretty sure they weren't psychosomatic. They were bad enough to cause me to shoo the gamers out early, and lasted for several hours. In fact, they were bad enough to wake me up later. That, combined with them showing up on exactly the right day leads me to believe that they were real after all.