Why do I get these little pains under my chest?

Answer:
No enough info. How old are you? Where are your pains in addition to your chest?

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Though you're not very specific about your problem, it could be that your bra is too tight (or your band size is too small). Remeasure your sizes, and go shopping (or get bra extenders, available in sewing stores/sections of stores). When your bra band is really a lot too small, it starts compressing your rib cage, which can be mildly annoying at first to extremely painful at the worst.

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Because I'd feel remiss if I didn't say this--chest pains can be pretty serious, so don't hesitate to call a doctor if you are worried.

Now that that's out of the way... :-) It could be that your bra is too tight. It might also be a digestive thing--is it often after you eat, drink soda, or eat certain things? If you've had a cold recently, I've found that having coughed a lot can make my chest/ribs hurt for a few weeks.

Depending on where it is that you are hurting, it could be enlarged lymph nodes, a tender spleen, gallbladder, stomach, or any number of body parts.

webmd.com has a little symptom checker that might have some more options for you to consider.

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