Definitely. However, I've heard that this is also a side effect of menstrual cycles for some, or if you're using birth control pills. It really depends on the person. If you don't normally feel this...
I dont know i dont understand i havent had sex or a baby and my brests are tender and my nipples are sore and hard. :(.
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dno about the pregnancy one but the girl who has hard nipples is a retard