So you can't start to show at 8 weeks?

I ask this because when I bloat it is on and off, but all day today from the time I woke up my tummy seems like it's showing a bit. I showed my mum and she felt my belly and she said "yes, its definitely hard" but everyone is telling me that you can't show at 8 weeks unless you have had children before. Whereas people I know have started to show at 8 weeks with their first :\ I am getting mixed signals here, because my belly has been this size all day.