Hi J.---You didn't mention whether or not you've had morning sickness. I did will all 3 and until 20 weeks I was losing weight. Funny thing, once I started feeling better, I put on 10 lbs or so the next month. As others have shared, your weight gain will vary from month to month.
If you are eating mostly fresh fruits and veggies, whole grains, beans/legumes, nuts and seeds while keeping animal protein to 10% of daily calories, you and that baby will be optimally healthy. Animal protein, and dairy, contain mostly fat and calories and too much contributes to degenerative diseases such as cancer, heart disease and autoimmune disorders. What you eat now will determine your baby's preferences when he or she starts to eat solid foods. There was a great article in the Oct 4 issue of Time magazine about how you eat now, during pregnancy, determines the diseases your baby might be vulnerable to as he/she ages.
http://healthland.time.com/2010/09/24/how-the-first-nine-.... Other sites to explore: www.pcrm.org and then put dairy in the search box, but do explore the entire site and www.chinastudy.com.
I apologize as it seems as I may have gotten off topic a bit, but how you eat determines MANY things relating both to pregnancy weight and health AND long term health for you and your family. If you would like to know anything more about the topics I've raised, please feel free to contact me. Our docs really don't know too much about how nutrition impacts our health and nutrition should be the first place we start with any health problem. Thank you for letting me share. Hope that this helps. Be well, D.