Hard to say boysway! maybe he was expecting bigger? I always do my own fundal measurements at home since I only see my OB every 4 weeks. It keeps my sanity in check that shes still growing in there. If you run your hand straight down your ribcage eventually you will hit a hard spot and thats the top. Measure from there down to your pubic bone and whatever the centimeters are that should be what week you are plus or minus 2cm. Its not an exact science but if you know you are 25 weeks and only measuring 18 then you have an issue. When they do mine in the OB's office I always ask them how many centimeters it was just to make sure I am measuring accurately myself. If you are 20 weeks and above you should be above your belly button or getting close to. This of course only works for 16 weeks plus.
