Just a nasty indent I am guessing?

So I thought I saw a faint positive on a walmart cheapie 88 cent yesterday. So today I took a FRER with FMU, faint but noticeable line. So I thought for sure the Walmart cheapie would have a more noticeable line. Nothing 😥

So I took another FRER with SMU (about 2 hours later) same thing, faint but more noticeable line. Used the SAME urine sample and took another Walmart cheapie and NOTHING. I officially hate First response. Here are the pictures.

FMU faint but noticeable

SMU

Both Walmart cheapies, nothing