J.C.
I got my periods back 3 months after the birth of both my girls, and was pregnant right away (only one period) after my first. After the second, my period was pretty regular right away. It can be different for every person though. If you are worried about possibly being pregnant, I say take a test as it is very easy to get pregnant after having a child (even while breastfeeding). I know all about it, my girls are 13 months apart :-)
Good luck!