A: The answer here depends on a few factors. First of all, women pregnant with their first baby tend to show later than women who have been pregnant once or twice before. Some women pregnant with their first babies may not show until 20 weeks, a time when the top of the uterus is finally at the level of the belly button. Women pregnant with their second or third (or more!) child will often show earlier because the tissue holding the contents of the abdomen in place (the fascia), has been stretched before and gives more easily, allowing a growing uterus to "pop" out earlier.
The height of a woman (taller women tend to show later), the amount of weight gained during a pregnancy, the presence of more than one fetus, and the depth of a woman's pelvis (the deeper the pelvis, the later one will show) are all variables that can also affect the timing of when a woman will finally look pregnant. As long as your practitioner is keeping an eye on your baby's growth and your overall weight gain, it doesn't matter what you look like to yourself or others!