Feb 26, · Pregnancy can also cause breasts to be swollen, sore, and tender. In addition, both PMS and pregnancy can cause the nipples to be more sensitive. However, breast pain and soreness from pregnancy Author: Danielle Dresden. Jul 15, · Breast pain is often the first symptom of pregnancy, occurring as early as one to two weeks after conception — technically, weeks three and four of pregnancy. That sore boob sensation peaks in the.