Considering a breast reduction - should I be concerned about raised bump on nipple? 5'1, 200 lbs, DD cup.(photos)

The small bump appears to be a benign cyst. You would want to confirm this prior to the breast reduction surgery. I would suggest beginning with your primary care physician who can refer your to a dermatologist or surgeon if necessary.

Any new nodule/bump should be evaluated by a physician to rule out any concerns. From your photos it appears you would be a good candidate for a breast reduction. If the nodule is benign it could be excised as part of the procedure. The next step is to schedule a consultation with a board certified plastic surgeon near you.