Faint Positive Pregnancy Lines (Coming and Going - Confused!! 🤨)

Ok ladies I’m breastfeeding (with a forumla bottle here and there), and I’m 7 weeks postpartum. I had sex using pull out method a four times over the last 15 days. Last Saturday I took a test before starting my mini pill. I saw a faint positive so I didn’t start the pill. After a few more tests came up negative I assumed that was a weird fluke and I wasn’t pregnant. Here is the test from Saturday:

Looks positive to me, same day took a FRER and there was absolutely no line. I also took another one of the Walmart tests the next day and no line.

Today I took my last test I have at home, a FRER because I felt kind of crampy the past couple days.

Now I see a faint line on this FRER!?!? It was hard to capture but def there within the time.

Ok so at 7 weeks PP could this just be my HCG leaving my body? Could this be a new pregnancy? I’m just confused....