Breast concerns?

Okay so I apologize if I’m not necessarily posting in the right place, but, I was curious as to when I should be concerned about an achy/sore/ itchy breast? Like there’s no obviously lump or anything. But there is a tiny bump in my armpit (not very big) that I can feel if I’m sitting just right. Last week I had an itchy arm put that slowly spread to my breast and my breast had been aching for quite some time. If it were hormones, wouldn’t my other breast hurt too? I’ve already been to my doctor about it and was told it was nothing to worry about. This has been ongoing and I’m scared to go back in in fear of feeling dumb about it.

Has anyone had the same issue, and at what point should I be concerned! TYIA