Hi Jacqui,
You are felling just as all of us have felt, and there is certainly no competition here about who has the biggest tumour, and therefore the right to feel worse than anyone else! We have all had that sick feeling when the diagnosis was given, and it had nothing to do with the size of the tumour. No one who has not had the words 'You have cancer' said to them can truly understand the impact of hearing it, so matter how sympathetic they are.
All you can do is go down the route your doctor suggests. I have private health insurance, and asked a friend who has had breast cancer if she would recommend using her breast surgeon which she did, and I am very happy with her. A friend with private health was equally happy with the surgeon assigned to her by the hospital. Your GP will give you the referral.
Your breast surgeon will tell you your options related to the size of your lump, and will be wonderful, as is the breast nurse, if there is one in your area. You can't find out if chemotherapy or radiation will be necessary for you until after the tissue taken from your operation is analysed, and the specific type of breast cancer is known.
The time that this will take out of your life this year can't yet be known, but be aware that this support group is here for you and will answer any questions that we can from our own experience.
Good luck and keep us posted on your progress.