Hopefully someone can help me

Hi ladies, will try to make this short. May 13 I had a MMC at 11.5 weeks. Had a d&c and by beginning of July I still hadn’t gotten AF. I took a pregnancy test July 11 and that’s what you see in the top photo. I knew it wasn’t a new pregnancy bc we held off having sex bc I wanted to wait for AF to come at least once before trying again.

After that test (same day) I went to the dr to see if there was any leftover tissue. Ultrasound looked fine. Then again same day I took that test (July 11) AF ended up showing that night.

Fast forward to today, July 28 and CD 18 I took the bottom test. And STILL FREAKING POSITIVE!!! Wtf. Dh and I have DTD a lot since af ended but there’s no way even if I O’d CD 14 that I’d be getting a positive. Has anyone had this happen before? I’m praying I get pregnant again this cycle but I’m just so confused on how it can STILL be positive. Even after getting af!