34 week scan, head size measuring two weeks ahead...

Hello everyone!

Today I had my 34 week ultrasound scan. The tech said my little man had a healthy heartbeat, weighed about 5 lbs, and was measuring normally. Expect for his head... She said his head circumference was measuring 36 weeks. But my doctor told me that she didn’t see any extra fluid in his brain and that it might of been a miscalculation. They are having me back in about three weeks for another ultrasound just to check and see if he is still measuring ahead. The doctor didn’t seem concerned at all but I’m very paranoid that something is wrong! I have a rather large head and my siblings also did as well. But my boyfriend was average sized. Maybe just genetics? Just wanted to see if anyone else went through this and what the outcome ended up being. Just need a little reassurance because this is my first pregnancy and I worry about everything when it comes to my baby boy. Thanks!