Yes, I'm 8 weeks with my fifth, and I'm showing. It's that your uterus' muscle are already somewhat stretched and therefore don't need the extra time for preparing the womb...I like showing early!!
Yes, because your body knows the drill
Seeing as how your uterus remains so low early on, it's highly unlikely that an early bump is actually your baby. It's usually a result of bloating and constipation from intestinal changes.
Some ladies do and some don't I'm pregnant with my second and I being showing since I was 13 weeks