Positive and negative with same pee?


I am 7.5 days past my frozen embryo transfer which is about 12.5 days past ovulation. I took a test this morning with FMU and immediately saw the second line. It’s pink in person. I then got out another FRER because I didn’t believe it. I used the exact same pee and it was negative! I cannot figure this out. Is the “positive” just an indent?

First test:

Second test: