Can anyone help me try to explain this...?

[bluemoon2468]

So for a bit of background, I'm CD20, and supposedly 4DPO. The first picture is my chart this cycle. I had positive OPKs on CD8, 14 and 15, and two rises in temp (which happens to me every month), but Natural Cycles ignored the first one and says I ovulated on CD16. Today my temp took a massive dip as you can see - if it were in a few days time, I'd say possible implantation dip? But it's too early. This never happens to me really - I've attached two of my other charts from months I wasnt pregnant for a comparison.

Can anyone shed any light on what might be going on? Thanks.

I've also had big dips in my tww- it's a random oestrogen surge apparently. It's more common in pg charts, but happens in non-pg charts too (like mine). So could be something, but might not be. Fingers crossed for you!

@Sammyclaire22 thanks so much for your reply! That's hopeful then - glad it's not a bad thing!