Has anyone else had this??? What was it?

hello, I was diagnosed stage 2 right breast idc her 2 positive in November 2016. I completed 6 rounds chemo, lumpectomy with radiation and one year herceptin. I finished rads end of September 2017 and herceptin December 17. I just had 6 month ultrasound. Result was recommended ultrasound for “well circumscribed oval mass with architectural distortion and skin thickening of the Breast” the doctors notes state “looks very likely to all be post surgical” and “mass in upper right Breast likely represents post surgical fluid collection.” Has anybody ever had this experience?? I’m trying to be calm. Please answer!! Thanks!!

Thank you for answering!! Did you have a mammogram with similar results to mine