FRER lines

Just curious but I noticed frers lines are thinner? Makes it harder to distinguish the difference between an indent and a bfp.

I took a test last night on a whim after having a really odd 9 day period. There was a super faint line. Took another this morning with fmu and it was darker more pink.. pretty convincing.. anyone with a bfp had thin faint lines like this?

Yesterday’s test

Todays test