Breast and nipple changes

I know your breasts and nipples change during pregnancy. But my nipples hurt, more like a burning sensation when it’s cold, to the point to where I want to cry. They also stay red. I’ve brought it up to my doctor and he told me it’s part of pregnancy, which I know. But the thing is, they’ve done this since before I got pregnant. My nipples have been red since before pregnancy as well. Nothing is coming out of them. I’m 28 weeks and I go back to the doctor next week. I’m going to ask him again and hopefully he’ll hear me out and not cut me off like before to tell me it’s part of pregnancy. But has anyone else experienced this, even before pregnancy?