Honestly, ang Blue Doctor HCG ay magbibigay ng estimate lang based sa HCG levels, pero hindi siya super accurate kung hindi mo alam ang exact date ng conception or last period, kaya kung out of track ka talaga, makakakuha ka ng range of weeks lang, hindi pinpoint dating. Ang safest approach talaga ay mag-ultrasound na lang with your OB, kasi nakikita nila talaga ang baby at bibigyan ka ng more accurate dating from there, a few of us tried relying on HCG numbers lang and ended up confused pa, so don't stress and just book a check-up na para sure!