when did you start showing!

I found out I'm pregnant two days ago with my second. YAY!!! I had a feeling I was as the last few weeks I have been feeling a little different. I already feel like my belly has popped out a bit 😮😮 can this happen?? Lol I'm 2-3 weeks according to my test and doctors terms I'm 4 weeks!! 
When did you start showing with your second?