This isn't what you want to hear, but it just sounds like a funky cycle. Either you ovulated later than you think (and your period isn't actually late) or you're just having along luteal phase for some reason. Given that your IUD was removed less than a month ago, I wouldn't worry about it.

I say that as someone who has also gotten pregnant on the first cycle every time trying. I have a cycle you can set your watch by and a few months ago I ovulated on CD10. Totally unusual for me, but went back to normal the next cycle.

I got my (non hormonal, copper) IUD removed on Dec. 7. I was ovulating, according to the testing strips and my app. I had sex that day and again on the 9th. My period is currently three days late, it’s day 31 of my cycle, but I took a pregnancy test last night and this morning and both were negative.

Could it still be too early to test?
Could test be faulty? (Frieda brand)
Could my IUD have messed up my period? Since it’s copper my OB said I’m fertile right away.

Age 36, got pregnant on the first cycle two previous times (two kids).

What could be going on?