It must be disappointing to be having this now when you have been doing this for a while. It could be a white spot - this is where the skin can block an opening in the nipple and milk builds up behind it. If you can see this spot you can try and fix it yourself. Start by soaking the breast in warm to hot (not burning hot) water, or use a warm wet cloth instead. Then try to loosen the skin over the blister by rubbing firmly but gently. More vigorous rubbing works better for some mums but can be very painful, and can also lead to bruising if it is too rough. Once the skin over the spot has rubbed off or been loosened, breastfeed or express to clear the milk and if there is a plug or thin strand of milk at the duct opening, wipe this off gently but firmly. If that doesn't work, a doctor can use a sterile needle to clear it.

If the spot doesn't seem to be a white spot (also called bleb or milk blister), then it might be thrush. A visit to your GP might help to figure out what is going on.

All the best hun.