Severe breast pain

For years now I get really sharp/throbbing pain in my left breast.

I've been told I have fibrous cystic breasts by my obgyn in the past.

This pain is specifically in the breast and not my chest.

The pain also moves around the breast. Physically going around it and sometimes moving towards my nipple or the base of my breast.

My doctor's just say it's nothing to be concerned about, but the pain is happening more and more frequently now.

I can have the pain for days on end now.

The pain also gets so severe I double over.

Any idea on what this pain is?