@Bearyfolk. It is a whirlwind sometimes and a shock and sometimes it takes some time for the emotions to catch up. Not sure if mine have, yet. Diagnosis on 5/12, wide excision on 21/12, mastectomy on 8/1 and heading in this week for my second chemo. As everyone else has said, there's a wide range of emotions and there's no "right" response to this. I've been through shock, tears, disbelief, anger, depression and fear and back again. I will say that after surgery I thought that I felt fine (not sure if I really did, though) so maybe this is it for you. Or maybe down the track it might hit you. If so, lean on those who support you.
Best wishes.