Second Pregnancy

I am just about 4 weeks pregnant with my second child.  I jusr had a miscarriage two months ago and of course is making me a little more nervous.  I told everyone and then had to tell everyone that I lost the baby.  I am now 4 weeks pregnant again and nervous about telling everyone, even though part of me wants to because I am so excited.  I was hudge with my first and noe I am 5 foot 6 and about 155 pounds and am wondering when I can expect to be showing the second time??  I want to tell people before the notice on thier own. I heard it you start to show much earlier the second time.