Y'all, my boob hurts!

I have been undeniably blessed in regards to my breastfeeding journey. My son had no trouble latching within 20 minutes of birth, my milk came in with a vengeance after four days, and I've suffered almost no nipple or breast pain. Like I said, blessed! My son is now 4 months old and EBF. He's never had a drop of formula.

But by the end of the day yesterday, I noticed that my right breast is very sore and tender to the touch. Especially in what must be the milk gland areas. It isn't red or swollen that I can tell, and I still seem to be producing. Can anyone tell me what may be going on?

Here's a pic of the little chunk! He's so adorable I can't help but share him. 😁