Valerie, first of all, don't worry about breast cancer; at your age, it's virtually impossible that you have it. Please read our message to teens about breast cancer; I think it'll make you feel better.
If both breasts hurt, which you seem to be saying, it's most probably a sign that they're growing. Sore breasts are usually the result of hormonal activity, and hormones are active during puberty; our teen guide to breast development will tell you mre about that.
As for the sore red spot on one breast - you might have gotten a bug bite you were unaware of, or you might possibly have an infection. The only way we can help you with this is to suggest (strongly suggest) you tell an adult, someone you trust. Your mom, a friend's mom, or an older sister can help you figure out if this is something a doctor needs to see. If it's getting worse (bigger, redder, more [painful), then certainly you need to see a doctor to have it treated. So get some guidance from someone older, OK? Good luck - I hope you feel better soon. PJH
Sounds like you might have an infection, Valeria - or possibly a bug bite, as I mentioned. I'm so glad you told your mom - moms want to know about your health issues, so they can help. I hope the doctor will set your mind at ease that this is nothing serious, and treat it if necessary. Again, good luck - PJH
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