Measuring ahead measuring behind !!

Anam • 💙💙💙

So I went to radiology at 12+4 days.. and my technician said baby is measuring 13+3 and then my doctor changed the dates.. then I had a scan at 17+2(according to new dates) due excessive pelvic pressure and severe cramping and BAby was measuring 17+ 4 .. so basically always was measuring ahead.. today I had my anatomy scan at 20+5 .. and today baby is measuring 19+5.. I don’t get it one whole week behind.. did that happen to any of you guys ??