I need advice!

Preface: I have irregular periods and tracking my ovulation days & expected period days is more difficult then I thought.

I was what I thought a few days late on my supposed to be period. I took a test Monday, it came back positive (clear blue digital). I called my doctor to get blood work to confirm and it came back negative. I still have not received my period and have not had any symptoms, but I just feel pregnant?

I’m curious if my ovulation date could have been different than what I originally thought, & I could be pregnant but not able to detect yet because too early? Or am I just paranoid/hopeful and making my period prolong? I’m really hoping my ovulation date was different and I am pregnant, but I feel confused and could use some advice.

Also, why would it show up pregnant then the bloodwork show negative??