I Am 38 Weeks Pregnant. I Am Dilated 2cm 50%

I am 38 weeks pregnant. I am dilated 2cm 50% effaced -2. My Dr is worried that because my torso is short and the baby is larger than expected, she won't have much room to move or enough fluid. I'm scared because he wants to do an emergency sonogram tomorrow. What are the possible results due to what he finds?