Burning Breasts

At about 3 1/2 weeks pp I started to get a burning sensation and my nipples were hurting. I got the burning really bad after breastfeeding but it came and went all day. I went to my 4 week appointment and she thought it might be a yeast infection. I have no rash or anything. She prescribed an anti fungal and it helped but the burning never went away fully. I called back at 6 weeks and she gave me more doses. It helped a little again. Now I am 7 1/2 weeks pp and they are still burning and my nipples are still pretty sore. They get worse after I breast feed. Has anyone had this happen to them? What else could it be. I have not had flu like symptoms, no rashes, no fever. It is driving me insane though!