I've had a bump since 3 weeks!!! I know, crazy! I am in a similar position, normally flat tummy, very fit and healthy, run and go to the gym, and so I was shocked to find my seatbelt not fit properly over my belly and my pants at 3 weeks! Since then it has got slightly bigger but not much, It is usually a bit smaller in the morning, and by afternoon it can often be quite bloated and of varying sizes.
I am 11 weeks 5 days now (DD 23rd Oct) and I can see a second fold line which means I think I'm about to get a bit bigger.... I'm tired of trying to hide it now and am happy to wear fitted tops again if I feel like it :-)
I had 2 m/c last year so I think that is a contributing factor to the size of my belly as each time is popped out sooner until this time I knew before evena pregnancy test could confirm it.
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