Period supposed to start tomorrow but positive ovulation test?

I mean the title pretty much explains it y’all. Here’s the backstory:

Last night BDing with my husband I started bleeding. My period is due on Saturday. Of course my brain is like

So I go put a tampon in and sulk back to my bedroom all pissy and mad cause that means this month was a BFN.

Well fast forward a couple hours I gotta change the tampon. I take it out and it’s stark white. So I’m like

Didn’t wear a tampon at all today. No bleeding at all. Got home from work, thought, “maybe I should take an ovulation test for shits and giggles?” Because I only had two left from this package. So I take both of them and they’re both positive.

So my question is, what in the hell could have caused the bleeding and why are ovulation tests positive now? Shouldn’t I have ovulated like a week or so ago? Any help is much appreciated.

Unrelated possibly but: I had a full Pap smear, mammogram, and ultrasound three weeks ago and they came back clear.