I guess it depends on what you weighed pre pregnancy. But your body does hold a lot more water, extra blood,stored fat for the baby, placenta uterus, all that. You'll drop like 30-40lbs instantly after birth. Don't stress too much. I was 160 pre pregnancy and reached like 198 when I was giving birth. I was devastated, lol but it went down pretty quick.
10 pnds is guaranteed your babys weight & you'll prolly lose more after birth. If your feet & hands look swollen then most of it could be water weight! Also, if you breast feed that'll help with losing baby weight too.
I'm in the same boat.
My Dr said it's just the body holding a lot of water, so you should bounce back pretty quick after baby is born.
I wouldn't worry too much about it :)