It should go away in afew days to a week if it doesnt or if it gets bigger then you need to go to the drs that happened to me it will hurtbut 99 percent of the time its nothing just give it time
I experienced the same thing under my right arm while pregnant with my 2nd bacj in 2011. My doctor kept saying a clogged milk duct but I was concerned because it wouldn't go away. But it was because of me breastfeeding. It finally went away after I stopped breastfeeding my 3rd Son. Sometimes it would hurt and sometimes I could barely tell it was there
Omg i got that too.. but im only 15 wks so i wouldnt know if is the milk... i did go to the er because it was hurting a lot but unfortunately because im preg they were not able to do any xrays or ct scans..
See your Dr. You cant assume thats what it is.
I would make a visit to your family doctor
I'm sorry no wish I could help answer your question.