Lopsided breasts! Help!

Hi mommies, so my Lo is 4 mos and I've been breastfeeding him since birth. Around 3 months I had mastitis and ever since I took the meds I was prescribed and it healed up my right breast just refuses to fill up anymore, I have enough milk in my left but it's not only frustrating that I'm not making as much as i used to I'm so lopsided that ppl stare because the difference is crazy. I've tried power pumping, more liquid intake and making him latch on the right more but nothing is working. The most I'll get is like 2ounces because it starts hurting and I feel like i have no choice but to pump it out, it's really killing my drive to push through bf. Help please!