Is there any test you would believe a negative 100%

I have been having VVVVFL since 8-9 DPO .

The lines not getting any darker and I’m now on 12DPO . I’m taking ‘one step ‘ tests because I’m a terrible serial tester and have used these for a while . I’ve never had indents on them before but I’m wondering if I have had a bad batch 😔 .

I also took a clear blue 10DPO that was negative .

I have FRER coming today which I will take but I’m so confused , this has massively fried my brain .

If the FRER is negative would you believe it and just except the one step cheapie tests were faulty ?

OR keep up the hope until AF comes ?