Extreme nipple pain?

Bri

My LO is about 6 weeks... and just yesterday I started getting extreme pain in my left nipple. From the outside, it looks normal. But even when she’s breastfeeding or not, I have a lot of pain in my left nipple. What could this be? Planning to take ibuprofen and wear a more supportive bra so I don’t feel the pain so much. It’s is so painful!

My right nipple is still totally normal and feels fine.