Hi @Della I could only wash with a cloth initially, and then I was told only very short showers/try to keep water off the dressings (which were water resistant). Once I felt up to it, I got my hair washed at the hairdressers as I couldn't stand it after about a week of not washing it!
Hopefully the hospital has made an appointment for you with oncology in a couple of weeks, as well as your surgical follow ups. By the time you see them they will have the full pathology from your surgery. This tells them a lot more than the pre surgery biopsies and MRI. The MRI can't pick up traces of cancer, for example in the lymph nodes or other locations in the breast, that the microscope can.
Hopefully your recovery is going well. I found that incision for the node biopsy the sorest part - so many nerves there, says my surgeon!