okay, further thoughts
Is there a chance of yeast infection? Have you been on antibiotics lately? Have you started eating or exercising radically different than what you were before? Have you gotten your cycle back? Some women experience discomfort/pain in their breasts just before the onset of menstruation.
If none of these seem at all likely, I would recommend seeing your doctor for further trouble-shooting.
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If you weaned rather quickly, that is taking away more than 1-2 feedings a week, then it might be mastitis, ie - a clogged duct or breast infection.
Is it localized? Or all over that breast? Is it warm to the touch? Is it firm? Is there a red spot? If you take your breast in your hands and massage, do you feel a knot or hard spot? Do you have a fever?
If it is a local, firm hot spot then it is likely a clogged duct. Use heat - warm compresses,heating pad, hot shower water - and massage with your hands. Start at the chest wall and massage outward towards your nipple. You can use sage teas to dry up your milk. Also - and this sounds awkward - get some cabbage. Place one leaf on each breast and inside your bra. As soon as they wilt replace with fresh leaves. This is another thing that will help dry up your milk.
Even though you've weaned dd, your breasts will still have milk in them for a while to come. The lactating breast is never truly empty. Make sure your bras fit well. If they are tight at all, then they can cause a plugged ducts.
Although your dd is no longer nursing, I would recommend pumping to help the duct get unplugged. If it's a plugged duct, 'm afraid if it just sits there that it will begin to fester and turn into an infection.
If you have a fever, you need to go see the doctor.
That's all I can think of for now. If something else comes to me I'll add it to this post.
HTH
K., mama to
Catherine, 4y
Samuel, 14m