Huh?

So a few weeks ago at my doctor appointment, the doctor said he was worried about how small I was measuring. He decided to order an ultrasound for me. I was not about to tell him that I measured small with Jenna and she was 7 lbs 5 oz when she arrived. I figured it was my chance to see the baby again before he was born without paying an arm and a leg to go to Fetal Fotos. So mid-June I went in for the ultrasound. The ultrasound said that he was measuring about 5 lbs--in the 61st percentile, so a bit on the large side. The doctor still measured me at 3 weeks smaller than I should be. So the baby is measuring big and I am measuring small. Should I be nervous about this??? I think this explains all of my growing pains, though.