Large lump in breasts

I need advice because I just moved and don't yet have a doctor, otherwise I'd go see my regular doctor.
I've noticed that around my period (sometimes even 1 week before my period starts) my breasts hurt MUCH more than usual. Not my nipples so much, my breasts. It's mostly on the outside of my breasts, almost near my armpits.
I'm laying down without a bra on and I happened to notice there are large masses in both breasts exactly where they've been achey. The masses hurt to touch.
They feel lumpy like milk ducts, just swollen. So swollen today that they're almost visible when I lay down because everything kind of sinks down.
 I'm not pregnant or breastfeeding. Has anyone else had this? Is it just caused by hormone fluctuation during my period? My body has been doing lots of weird things in regards to my period lately. My periods are heavier and much more painful, even my body has made a change, I'm curvier and just more womanly overall. 
Please give me some insight. I've always known my body and understood what was going on, now it feels like it belongs to a stranger. (I am 21 years old)