I Have Tiny Red Dots On My Breast, Last Night

I have tiny red dots on my breast, last night they area was itching badly, so being a human I scratched the spot until I was satisfied, and after 15 minutes red dots started to show up, and are still here what are the dots? There are like 15 of them...it's like now it doesn't hurt, and it's under the skin , not like a pimple