Measuring Small

Eboni
So today I go to my 37 week appointment. I have been going every week since last week, but today I had a new doctor. I carry more so in my torso, but my belly measurements have always been spot on at every appointment. Today, however, the docgor pulls out the measuring tape and asks me how far along am I. After I tell her she says that I am "measuring small". I tell her that I have never had a problem before. She says that she is going to check my cervix and then order me an ultrasound. I was 0 cm dilated again. The ultrasound tech was available so I was able to see her immediately. She did some measurements and movement test for about 30 mins. The results came back that I am in the 7th percentile for my baby girl weighing 5 lbs 6 oz and at 37 weeks, they would like for moms to be in the 10th/11th percentile. Movements and length was perfect, just not big enough. I was told that she should gain about 1/2 pound a week at this point. I was then told that I will be scheduled to see a specialist to confirm these measurements and I will have to get a ultrasound for the rest of my weekly appointments. I was frustrated because everything has been fine until now. I have gained more weight in the last month then in my whole pregnancy. I eat more and drink more water because of my feet swelling. I have always asked about the baby's weight but was told she was on track to weight 7-8 lbs. 
Just want to know if any other moms have had this issue and how was your delivery with smaller babies?? 
I'm a FTM by the way!