Measuring at 36 weeks two weeks straight w/ weight loss?!

FirstTimePregnancy

I just got back from my weekly appointment and am measuring at 36 weeks fundal height, which is where I am at....but I was the same measurment last week (prior to that, I had always been measuring at least a week or two ahead).  I have also lost 3lbs. since last week but the nurse says this is nothing to be worried about as long as the baby is growing.  The doctor said everything looks good....but since leaving, I just realized that the measurement is the same as last week and having lost 3lbs. on top of that I am concerned.  I'm not sure if the doctor noticed the measurement being the same and weight loss and wasn't worried about it or if he missed this since the nurse took my weight before he came in.

Has anyone else experienced something like this?  Do you think I should be concerned?