Hi, I am a 18 year old male. About 2 weeks ago my nipples started to become very sensitive and after a little while they started puffing up. Now they aren t as sensitive but they are pretty puffy and big. It s really annoying, especially when I go to the gym and they show through my shirt. I m a pretty built guy but my nipples detract from my image a lot. What is the cause of this? Will it go away on its own or is this serious and should get checked out? Thank you and I look forward to your responses!