Breast cancer

on July 7th I was diagnosed with breast cancer, on 6th sept had surgery, lumpectomy and reduction on good side. I am due to commence of chemo over the next 18 weeks then 15 sessions of radiotherapy. I am still overwhelmed by it all as I  never felt ill, whilst now all i seem to have is a lot less energy and bruising of the chest which is still quite sore and swollen

is this normal, as everybody who I have known have cancer had been quite poorly