Firtility Friend chart help


First it said I ovulated on day 15. Which I agree as I had ovulation pains on day 14 and EWCM on day one 15. Then it moved to day 20 probably because that’s when my temp started rising properly. This morning it moved to day 25. I thought that dip at day 25 is the implantation dip. My normal cycle length is 30-33 days long. I took a pregnancy test yesterday and it was negative. When did I really ovulated? I didn’t use opk this month. Last month opk was at peak on day 14. Help please? Thank you.