I had surgery about 7 weeks ago.
Glad to hear you are happy and doing well depite the swelling. The only thing I can think of is maybe you are over using your arm on the swollen side. If you are right handed and is it your right breast? If you are lifting something heavy on that side, i.e. a child on your hip, something repetative, etc. If none of these fit you, I am not sure why this would be. I would call your PS and talk to one of the nurses about it or the dr. Also whenever I had some swelling, I kept a bag or 2 of frozen peas handy and that worked really well to conform to the breast and other areas.
Good luck and keep us posted on how you make out.
I am at three weeks post op. My left breast is a bit more swollen than the right... I think its normal for up to three months .