I was the same i am quite small myself and i didnt hardly put on any weight, my bump was small and neat! The midwife kept telling me i would have quite a small baby, about 6lbs.
It was only in the last month my bump did suddenly get a lot bigger but still they said it would be a small baby. I had a shock when he was born 8lb 6oz and he looked huge, but absolutely gorgeous! I know a lot of babies are much bigger but i am really small and didnt expect it!
Its not true about smaller babies being easier to get out, i know some who have struggled. Its the head thats the hard bit to get out and thats not usually any smaller.
Good luck though!