What changes can I expect in my body in the second trimester?

Quite a few. In the second trimester, the baby continues to grow, making room for itself by pushing your organs out of the way. So your abdomen will enlarge, and towards the third trimester other problems like hemorrhoids, heartburn and back pain may result. "what to expect when expecting" is one of many good prenatal education books to consider reading for more information.
See below. Your belly will get bigger you might have some lower abdominal pain you will get checked for diabetes you should get an ultrasound you will have a lower blood pressure.