You'll show around 20 weeks. I didn't really pop for this pregnancy until now and I'm 19 weeks. Just don't think there's anything wrong just bc you're not showing yet. I know that it's frustrating when people say "You're pregnant! Wow you don't look pregnant at all!" That's what I heard at the gym at 17 weeks. Now at almost 20 my belly has doubled in size. Only gained 5.5 lbs total though.
And my first pregnancy was totally different. I think it's because I've kept so active at the gym.
its different for everyone. When it's your first probably won't show for a while
I was 18 and weighed 120 pounds when I was pregnant with my first. I'm also 5'2 and I remember I didn't show for a while. At least until 16 weeks.. and others didn't notice my bump until around 18 weeks!
The less muscle tone you have in your tummy the sooner you will show.
Some women don't start showing until about 4 or 5 months some even later all depends on your body type and what number pregnancy being as it is your first probably will take a little while but you'll have that little bump soon no worries