Pagetts disease - opted for mastectomy with delayed reconstruction

I am also a newby to this ,found out I had pagetts of the nipple in November ,after loads of test they have found something on mru ,that they can't see on ultrasound.if I wait for more test it's going to be another 12 weeks,,my breast is now painful and very swollen. I've opted for a mastectomy, with delayed reconstruction. Worried