You have posted alot of questions and while I am a nurse and not a physician or research scientist, I will answer a few of them. Cancer is a mutation or abnormal growth of cells. Breast cancer is not caused by underwire bras, deodarant or lying on your stomach.
Pathology reports for breast specimens can take as long as 72 hours to actually complete all the testing. This is due to the multiple tests that are done to determine markers such as ER, PR and HER2 and others that will determine how aggressive the cancer is. Once the results are complete, they are sent to your surgeon who then will get them to you. Some surgeons may take time to visit with the treatment team before you see them again, especially in academic settings.
The type of biopsy you had, surgical versus needle will determine the length of recovery time. A small incision to the breast usually heals quite well in a week or two and if steri strips were in place, they usually fall off in the same amount of time. Soreness is usually minimal and lasts only a few days. If there is a bright red appearance, drainage from the site or you are running fever, these would be concerns to take to your surgeon immediately.
I do not know the answers to your questions about radiation etc.
I hope this information has been helpful.