I heard putting fresh cabbage leafs on them/in your bra can relieve them. I've never tried it but my older sister has. Also see your Dr could be an infection from a blocked duck
You can express a bit of milk just to relieve the pressure when it gets too painful. Also ibuprofin will help with swelling. The cold cabbage leaves should help. Avoid hot showers directly on them. Mint also decreases milk supply so you can try drinking mint tea.
I heard pineapple juice helps too. I would call your Dr. If you do not want to breast feed, they can give you a pill that will dry your milk up.
Wear a really tight fitting, supportive bra day and night and put cold cloths on them. A Dr will be able to tell if its an infection and give you appropriate pain killers. It will pass!
Eat drumstick leaves.. And mutton levers and garlic.
Hot water on a cloth was the only thing that worked for me wit my first pregnancy. I had a pot of hot water at my bed side BCUZ I was tired of running in the SHWR to run the water on me. I stayed naked all day bcuz every time they got swollen I was n bathroom...But I did breast feed but the pain of swollen breast is the worse felt like they were gonna burst!! Smh! Try the hot cloth n see if it works for U.