Welcome to the board. I had a mastectomy and no radiation, but I'm sure some others will respond. You can find a wealth of information by typing in "early stage treatment" or "Herceptin" in the
pull-down menu above. It is the tab third from the right, and you can type in whatever you are trying to learn more about.
Anyone who is diagnosed is scared. With the wealth of information on this board being scared will change to feeling empowered.
Herceptin wasn't available for me 5 years ago when I was diagnosed and I wish I had been able to take it.
Take care, and feel free to ask questions and get familiar with the search engine above.