well 1st of all congratulation on your 1st born.

well most of the women will take around few month to be able to get pregnant again. while a few might even start few weeks after giving birth.

the best time for you to get pregnant again in the medical point of view is around a year or two. it's after your womb is healed and able to carry a new one. but you may start earlier than that. and yes it will affecting you breast milk production.

as if you still breast feed, it should prevent you from getting pregnant if you breast feed exclusively (on baby-demand at anytime). but you may get pregnant. it's not a reliable method for contraception.