2nd pregnancy

Laina
I found out yesterday morning that I was pregnant with my second child after missing my period for 4 days. I was previously on the depo shot from 3/15 until 11/15. I'm a little nervous about finding out how far I am and how the baby is doing. When lookin for apps to help a lot of them didn't allow me to provide my cycle length so they all told me I was 3 weeks and 6 days. But when I put in all of my info including my cycle length it tells me I'm 5 weeks. Is this normal? Could I be farther along than I think I am? Anyone going through the same situation?