Big baby bump!

Olivia
I'm 12 weeks and have a very noticeable baby bump (with and without clothing). Does this mean I'm going to be huge?! I've read that people don't start showing until 18 weeks sometimes.. I know this sounds vein but if I'm already really showing how much bigger am I going to get.. Don't get me wrong I absolutely love my baby bump, it's just a shock! :)