What are the signs that you might be pregnant while breastfeeding? My son is 13mo and I have been EP for him. I am pumping 3x per day at the moment. Within the last week or two, my breasts have gotten bigger and I am having more output. I have not started my cycle yet, but my uterus is extremely sensitive and sore also. I took a pregnancy test, but it was negative. Could these be signs of early pregnancy?