Very little weight gain but measuring ahead

Madison • Mom of three sons! God answered our prayers and blessed us with a baby girl due 12/31/17 🎀
I'm 30w3d and just came home from my appointment. Throughout this pregnancy I've gained a total of 5-6 lbs but the doctor says I'm measuring more like 35 weeks. I don't know what's going on. I'll have an ultrasound at 34 weeks to check how big baby is and fluid levels. Measuring big is making me believe that I'll be having my third boy. We don't know baby's gender.