The below is info from babycenter.com. You can sign up for a weekly update with all kinds of cool info about the baby's growth and development. Just put your due date in and voila. I loved getting those updates throughout my pregnancies:
Your baby now weighs about three-quarters of a pound and is approximately 10 1/2 inches long — the length of a carrot. You may soon feel like she's practicing martial arts as her initial fluttering movements turn into full-fledged kicks and nudges. You may also discover a pattern to her activity as you get to know her better.
So, your baby is still quite small and has room to swim around in there. When you're not feeling the movements, she's probably toward the back of your uterus. As she grows, you will feel the movements more frequently. When you get to the 3rd trimester, your practitioner will probably have you do a kick count each day.