Painful breast bump!! Need advice!

Sorry for the long post! I hope you read it all and have some advice!

For the last 3 months approximately I’ve had a hard bump on my right breast that is very painful. It hardens a couple days before I start my period and that’s when it’s the most painful. The pain starts to go away as my period finishes and then the cycle starts again every month.

I breastfeed my child for four years, however, my right nipple was always more difficult for my child to suck on, meaning I didn’t feed him from that breast as often as my left breast. I was thinking maybe old milk that got stuck there? Has anyone else had this problem?

I went to the doctor and got an ultrasound. They said that it was just thick tissue and not cancer thankfully! But it’s very hard and painful, I don’t know if I should go back to the doctor and get another test.

Thank you all!!