Mastitis

My left breast is killing me. Its not as bad as the first day on my period since thats when it started and I've been massaging it as well as letting hot water flow down onto it. There's a lump as a little bit bigger than my palm in it also its red and warmer than usual. I was lactating even though I've never been pregnant(my nipple piercings started it) and I dont know what to do. My mom say is because of my irregular periods and my breast are fibrocystic but thats her reason for everything. Help please!!