With both of mine, I didn't gain much weight during the pregnancy, ended up 5 lbs below my prepregnancy weight with both of them (despite eating everything that wasn't nailed down), and then gained 30 lbs while breastfeeding-UGH! Hormones

. I ate much less while I was breastfeeding than I did when I was pregnant. Only lost 10 after my daughter was weaned, hit a high of 182 after my son, and am FINALLY down 20 lbs at 162. 30 more to go until I'm where I was before my daughter. If I lose 25 more I will be happy indeed. My son is 20 months old now.
Good advice from the posters above me. Definitely keep up with the vitamins, and focus on health, not weight. Also stop and enjoy the "baby time", it's over way too fast.