Due dates are calculated based on the first day of your last actual period, not from your missed period. If you are indeed 9 weeks pregnant, your fetus should be about an inch long -- about the size of a kumquat.
At 9 weeks gestational age a baby is approximately two to three inches in length and weighs less than an ounce. It has fully formed genitalia though it is still too small to see on an ultrasound.