My 6 month has a bump next to her nipple when i squeeze it yellowish pus came out. Its hard like a…

My 6 month has a bump next to her nipple when i squeeze it yellowish pus came out. Its hard like a lump. You can see the difference from the other one.. We took her to her pediatrician she said its hormones and nothing to worry about. But popped the first one next day another one formed. And it hurts her when you touch it...