HI and thanks for using the forum.
It is totally normal to have not had a period yet, especially since you are breatsfeeding. (I am breastfeeding my twins who just turned one and I didn't get a period until they were 11 mos. old) Many women don't get their period back until they stop breastfeeding (or at least start weaning). It is usually OK to continue to breastfeed if you are pregnant as long as you are not having pre-term labor/contractions (they sometimes suggest weaning if you are having this). It may be difficult to get pregnant while breastfeeding since some women don't ovulate regularly (or at all) while breastfeeding (due to hormones). If you are ready to start trying to get pregnant again, you should discuss this with you OB/GYN. Also, sometimes pregnancy can change your milk supply and babies sometimes lose interest in nursing when their mommies are pregnant. Good luck with the new baby- they are a lot of work but so worth it!