Bigger head?

Okay so I'm kinda freaking out. My baby was always low and as soon as I hit 30 weeks, and he turned head down, he went higher. My doctor keeps telling me his head is over the 97th percentile so he has a big head. Is it possible that he went higher up because his head doesn't fit in my pelvis? Which would mean I need a c section right ? Any other mamas experience this ?