Re: Pain in nipple without known cause
Welcome to the forum!
At this point, I think it might make sense to see a physician. I'm thinking you might have some sort of infection- that would explain the shooting pains, the swelling, and maybe even the hardness (if there's some sort of localized infection that is harder than the surrounding tissues). Thrush should be considered as a possibility despite the lack of apparent symptoms. Thrush is a bit of a chameleon, and can be present without the "classic" symptoms (white patches in the baby's mouth, red/pink/shiny nipples, cracked or flaking skin, etc.).
If you feel the painful area carefully, do you find any sort of hardened area? Maybe a pea-sized or smaller lump? I'm kind of wondering if you have a small cyst or a very small plugged duct in the nipple itself- hypothetically, when the baby nurses this little lump would be pressing against other sensitive tissues and causing pain.
Don't worry too much about biting. Biting isn't something that happens with all nurslings- many kids never, ever bite.
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