Baseball_mom! Hey girl! Long time no talk!
I've had FRERs like that and it was nothing for me... I personally hate the new FRERs because of my lines like that. It was just the indent for me --- but of course I'm hoping it is a true line for you. I saw so many like that turn to BFP, it's like it starts out grey clear line then gets pink. Soooo weird. But def my experience isn't everyone's, and I'm KMFX!
Sorry I'm not much help and probably more confusing. Keep testing!
Here's what mine looked like, if it helps:
https://i67.tinypic.com/frxy0.jpg