Whats the latest for bfp

I'm 5 days late having sum pregnancy symptoms but at home test bfn docs won't do bloods till another week after period late according to Emma's diary <a href="https://play.google.com/store/apps/details?id=com.glow.android.nurture">due date calculator</a> I'm about 4 week 3 days it was calculated by last period feeling down n giving up help