Positive pregnancy test on CD8?!

Baby

So this is the first time it has happened to me. I’m only CD8 my period ended yesterday. I took an ovulation test randomly (I usually get positive opk on CD16) and to my surprise it was positive. It felt strange so I took a pregnancy test and it was positive! So I got pregnant while I was bleeding? That’s so strange cuz my period was very heavy! Has this happens with anyone and was it a successful result?🤷‍♀️