Please help? Any ideas? TMI photo

Sorry I tried to block out what I could to still show what’s going on.

My period is expected in about a week. My breasts a very sore, which is normal for me. But today my right breast is more sore than normal. I look at it, and then see see this on my right under my nipple? Thought it may be a pimple but doesn’t seem like it. It’s sore. Any ideas?