I have had extremely sore heavy breasts for the last two weeks. My nipples have been sensitive also. This is not normal for me. It started about a week after my last period. I am 29yrs old and my cycle is like clockwork, every 28days. It has gotten si bad that I have to wear a sports bra to bed. I am sexually active with no form of bc other than the fact I only have one ovary and my uterus; no Fallopian tubes.the only other thing that is out of the norm is how tired I am. What could be wrong with my breasts!?