Walmart positive but negative frer?

Lizzie • Due in July 2019 with our rainbow after a loss on 6-28-18. Blessed with a 2.5 year old, 7 year old and 13 year old. All boys

Help!! Does anyone have any insight for me? So at this point I’ve had like 10 bfp lol. But I am worried because of two things. Frer is only showing a SQUINTER line compared to Walmart tests or even blue dye tests, I don’t understand why the frer isn’t picking up my positive like it should. Also, it seems that my fmu is not showing as strong as a positive as my afternoon urine is? Is that normal??? I am tempted to take a frer this afternoon just to see if it picks it up better! As of yesterday morning I thought I was having a chemical but now that I have clear positives on a Walmart test I don’t know what to think!! Do my Walmart tests look ok for 12 and 13 dpo? Thanks