18 weeks pregnant and having a sharp throbbing pain in the left breast that comes and goes but isn't tender to touch?

Breast exam: Anytime one notices a new mass, new pain, lump, bump or skin change in the breast it is very important to have this evaluated by a doctor who can help determine if any work up or testing is needed. Breast pain can be from hormonal changes, weight changes, dietary changes, cysts, changes in exercise patterns, ill fitting bras and others.