When my daughter was just a few weeks old, I remember standing in the kitchen and feeling a tingling in my breast. It didn't hurt, but it felt like your foot does after it "falls asleep" — a pins and needles sensation. About a second later? My shirt was wet with breast milk. Not everybody can feel their breast milk let-down, but some do, and others may even experience pain when it happens. Breastfeeding in general shouldn't hurt, but there are actually a few reasons for painful let-down.
It's always beneficial to reach out to a lactation consultant if you have questions or issues, but one of these seven reasons could be the cause of your painful let-down. By determining what could possibly be the issue, your solution won't seem quite as overwhelming.