Lump on baby's nipple!!

So i just noticed right now, as i was changing my 3 week old baby boy, that he has a large lump on his left nipple! He dosent cry when i tuch it but its very noticibe! Im so worried! I googled it and many moms say it's totally normal due to mother hormons given to the baby in the whomb, and that its more likely on babys that are being breastfed! Anyone out there heard of such a thing? 😥