No one answered you? yes thats most likly why because you gave birth 2 weeks ago. Usually it's the other way around for breast feeding moms but because your baby is so young he or she doesn't drink so much milk right now. I have been breastfeeding my daughter for quite some time now and she drinks alot! So much that i'm constantly drinking and still my pulse is high 95-105. That means I'm dehydrated- as long as your blood pressue is fine. The low pluse shouldn't be do big of a concern I'm no doc just a medical assistant. I would love to hear a follow up story on what your doctor said and how things came out.