Retesting

So I took a test almost a week ago and it had a very faint second line and I’m going to test again in a few days to see if it got darker. Fiancée and I just started Trying To Conceive and we had a miscarriage awhile ago so this would be our rainbow baby I just hope it sticks and I don’t miscarry like last time I lost the baby at 13 weeks here’s hoping we are. So should I retest early or wait until Friday my period is 12 days late I have a very regular 28 day cycle and AF shows up on time every month