Mirena and very faint lines?

Hi, so I’ve had the mirena for a couple of months now, I got it 7 weeks after having my five month old daughter. So lately i have been experiencing a lot of side effects, nausea, exhaustion, unusual cramps, spotting/bleeding, just all around feeling off, which I know is common with the mirena, I had taken a pregnancy test before and it came back negative so I just assumed this was my life now.. but a couple days ago, my step daughter out of the blue asked me “are you pregnant again?” And of course, me being crazy, i had to take a test, that’s when this happened.

Suuuper faint line, so I waited a couple days and took another one..

The line still hasn’t gotten any darker, two days later. But maybe I’m crazy, but I still see it!

Sorry the tests look so old, I took the pictures way late because I really didn’t think I was going to post anything about it. But it’s been taking over my mind! Haha so I decided to just post and get some other people’s perspective, thanks everyone!

Edit:

This was my first test with my little girl, so I think that’s why I started thinking something. Thanks everyone for chiming in!