Boob Problems

Hi everyone! I am 20w5d and I am experiencing a very tender right boob that seems to have a hard mass behind my nipple. It almost feels like a hard pimple that needs to pop. The left boob feels fine but was more tender a few weeks ago. I am wondering if anyone was experienced this? I’m thinking it’s a clogged milk duct but it seems deeper under the skin than what I’m reading about online.

Does anyone have any ideas on how to relieve this? My next OB appointment is in 10 days and I don’t think this is a super urgent matter. What do you all think?