I have no idea why people make comments on pg women appearing smaller, then at previous times..
This is my first pg (Well my first ended in MC.) I feel the baby move/kick/punch daily.. Not all my family live where I do and since this is the first child in my family & DH's family I send out regular updates of belly shots. Just before I went down south to see my OB everyone said that my belly in a photo looked smaller. And yep when I arrived they still reckon my belly was small..

Panic set in and I waited nervously to see the OB...
When I arrived at his office I begain to sweat. (Gross I know. But I was guessing maybe something could be wrong.) He checked everything out.. And then said "Bubs has so much room to move, But has moved quite a bit since last time, Nothing to worry about just sitting back. Perfect size but don't expect a 5 or 6 pund baby........"
Two days later everyone said oh how I had popped out all of a sudden, Wish they would make up there minds!!!!
As long as you feel movement I would ease up, Baby can feel your stress. If you are too worried try get into your OB earlier.. No point worrying and not doing anything about it.