Re: Blood from nipple?
I'd guess it's either a broken blood vessel, a blister, or a small crack. If you stop seeing blood and are not in pain, it was probably a broken blood vessel- they heal very quickly. If you continue to feel minor amounts of pain and see small amounts of blood, it's probably a blister or small crack.
Based on what you posted there are 2 other options which I think are less likely: mastitis and thrush. If you feel increasing pain and see more blood, pus, or red patches/streaks on the exterior of the breast, and also feel any combination of aches, pains, fever, chills, then it's an infection (mastitis) and you need to do your best to drain the effected side and also probably get a prescription for antibiotics. If you see more blood and feel more pain, including burning or itching sensations, and you develop fine cracks, then it's thrush and you and the baby need an antifungal medication.
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