S.O.
Sara and Kim are correct. Don't let one of the other posters scare you. With each pregnancy, there was more discomfort in the pelvic area. I was not able to walk or be on my feet as much for later babies as I could for the first one! I was going, going, going...for the first boy right up until the day he was born.
For subsequent pregnancies, I bought one of those belly bands! It helped so much! If you belong to a health club or fitness center or have access to a pool, go get in it and float / walk around a couple times a week. That also feels very good!
If pool not available to you, get in a nice full tub of water a few times a week and get some baby weight lifted!