Hello, and I hope I can help you today. Fundal height gives an approximate estimate of the baby s size... but it is not that accurate... We generally become concerned if the fundal height is more than 3 cm (3 weeks) off because all women are built differently and some discrepancy can occur. For example: taller women, or women whose fetuses are sideways look smaller than shorter or overweight women. The ultrasound is the more accurate determination of the baby and if your doctors told you the baby is actually big for it s age and that your fluid is normal (they measure that too on the ultrasound) there is nothing to worry about. So all this means is that your build or the way the baby is lying in the uterus is making your belly look slightly small. Regarding the protein in your urine, as long as you do not have high blood pressure, that too is completely normal during pregnancy as well. So as long as your prenatal care provider reviewed the ultrasound and did not tell you that there is low fluid, there is nothing to worry about. I hope I was able to adequately answer your question and that my advice was helpful. Best of luck with the rest of the pregnancy, Dr. Brown