OPK / LH Surge HELP

So gonna give a little background before asking my question.

So I started testing lh on CD11 got high on CD14 & peak on CD15. Also inseminated on CD15 (IUI). Now I’ve been continuing to test my opk after just to make sure my levels went back down. The opk have been negative but today I noticed the (test) line getting darker instead of lighter 🥴 and it’s not quite positive but it’s def darker than the opk from yesterday. I’m currently 4dpo, has anyone else experienced this?? Did I do something wrong?

On CD17 & CD 18 the lines were very faint but CD19 & CD20 the lines got a bit darker.

Please help lol I’m lost