So confused about DPO. Can someone explain this please?

According to my app, I am 3 weeks, 6 days. I had a positive ovulation test on June 15th and got my positive pregnancy test 9 days later. (I have not had a period since miscarrying in March).

Today I am 13DPO but my pregnancy test says 2-3 weeks past ovulation, meaning I'm 4-5 weeks pregnant.

How is it possible that I had my positive opk 13 days ago but the test says I ovulated 2-3 weeks ago.

Thank you, ladies!