At my first trimester ultrasound, the baby was measuring 12k, 5days. It was right with my last period to be due Jan 31. Now at second trimester, I had a scan at 19w but baby is measuring 17w. I was schedule again for 22w  5days, baby is super active but measuring 20w 5days. I am not worry bcos baby is healthy and everything looks normal, plus I am a small mama. Weigh 110 and height 5'5. New due date is Feb 15. This is my first baby.