Suzy with my first pregnancy i only gained a total of 5.5 kilos..and was 56.5 kilos at the end. I had a very small bump and received the same comments as you. Unfortunately my baby came premmie at 34 weeks due to a placenta abruption (had nothing to do with my weight or baby's size) and my DD was just off 5 pound. This was a very good weight for a baby who was 6 weeks premmie so i'm sure she would have been a good 7 or so pounds if she had of made it full term.

This time around my stomach is HUGE and i've been told that this bub is actually quite small, so outwards belly size doesn't reflect te size of bub.

Try not to worry too much - if you are only a slight person then it's unlikely you'll have huge babies anyway