big baby!

Just had an ultrasound done yesterday after I started spotting and cramping. Everything looks to be good, cervix is still closed. Still not sure why I started spotting. But now I'm nervous. I'm 25 weeks 2days. My little nugget is measuring at 27 weeks and 3 days. Could my due date be off? Or is he just going to be a big baby? Anyone have complications with having a big baby? The doctor said he looked fine and is growing just right. Just nervous he's going to be massive😂😂