Positive OPK after OV

Hi gals. So I know I OVd sometime yesterday because I bbt track amongst other signs. I took another opk this morning just to make sure and it was still positive. I included a pic below. My fingers are on the 2 most positive tests from Thursday night and yesterday morning during my LH surge and the bottom one is this morning...still dark. Is this normal? Or is my bbt tracking off? I thought the lines would start to fade after Ov. Maybe it takes more than one day to see fading? Thanks!