Talk to Gynecologist on Gestational Age

I had a Antenatal scan today and the report is attached my LMP is 16 dec ( i didn't get menses in NOV 2019 and dr prescribed me duphaston for 20 days one tab daily ,which i started from Dec 1 so at 16 Dec withdrawal bleeding started and continued for 7 days as normal menses after which i didn't get menses and on 11 FEB had positive Beta HCg test , so that marks LMP 16 dec 2019)

Report is good but GA is 7 weeks plus so radiologist said your confusing with LMP or you don’t correctly remember as you should be 9 weeks but gyne said its ok you are at right GA .

So i am confuse . I am sure about my LMP as i am following my cycle since 4 5 years.

Kindly reflect some light on report and matter

Thanks