Keeping your body in shape during pregnancy?

haha relax.. some girls, usually skinny girls, will drop right back to their size soon after pregnancy. i'm preggo as well - 4 weeks. & have a 2 yr old. everyone says i bounced back to my body quick after pregnancy. what's weird was i never even worked out hehe. but i did feed, which the doc said helps you lose the weight. & i would say just try to be active & eat right, i'm hoping after this baby i go back to my skinny self. haha