update on babies

I had a doctors appointment a few days ago and everything looks good. Somehow each baby gained a pound. One is 3.4 lbs and the other is 3.1 lbs. What I don't understand is how I only gained a pound, yet they gained 2? Someone told me my body must be working extra hard to keep these two alive and growing, and I probably worked it off. People have been very nice and complimentary about how I look, which I appreciate. But seriously I don't know how the babies are going to get any bigger in my body. The doctor measured my belly and it's almost the same as when I delivered Claire, yet I still need to make it at least 6 more weeks!!!! I've been lucky not to be on bed rest, but it's getting to the point where I basically am. I'm having to take people up on their offers to watch my kids. I keep thinking I can do it, but by the end of the night I have serious contractions. We're talking 2-5 minutes apart. So the less I'm on my feet the better, I guess.