Unfortunately, it might not be that straightforward.
So far I have 6 tests sitting in my little box. The darkest by far is from Wednesday, when I think I was 13dpo (possibly 11).
I have since tested again yesterday, the day AF was due, and again this afternoon - pretty much the same. No darker, perhaps a little lighter.
In the middle of that, I tested first thing this morning and got NOTHING. Well, that was my first thought. There may be a line there, but it is super light.
I have spend the morning reading forum posts from ladies asking the same things as me, 'Is it possible to get a BFN even when pregnant?' 'What does it mean if my hpts are getting lighter?' and so on.
My big fear at the moment is a chemical pregnancy.
There is lots of really helpful information out there about the sensitivity, validity, reliability, etc of hpts. The sensible thought seems to be that once you see a line, go to the doc for bloods and STOP testing! Due to a whole lot of reasons, tests can vary in their sensitivity. It's even possible to use the same urine and get 3 different results from the same box of tests. I honestly hadn't thought of it that way before.
When the box says, 70% effective from 4 days before missed period, I kind of assumed that if it picked you up that early, then ANY test would. But of course, the reliability of one test isn't based on the result of another. So it is possible to test negative, or have a lighter line, due only to the differences between each test. And then you have time of day, food and drink consumed, and all the rest than can effect the results.
I have also seen a few times that SMU can provide a better result than FMU. Given that I am peeing like crazy at the moment (you can see another post about my current symptoms here) I had been either testing at 5 or 6 in the morning, or lying in bed sleeplessly trying to hold on until a reasonable hour! I think I'll be testing again tomorrow with SMU!
So where do we go from here? Well, we are approaching this as if we are (still) pregnant. I have booked in for the doc next Thursday as hubby really wanted to come with me. By then, I'll be a week late and if AF hasn't arrived, we can go from there. If AF has arrived, I'll be grateful of the chance to discuss all this with my doctor.
Wish us luck! =]