Update. 5 days after I posted this question, my squishy breast became quiet. So it solved by itself. My body has been absorbing that extra fluid ghat showed up a week after surgery.
I wish the doctors tell us all about those small issues that can happen.
Thank you all who have answered. It help me staying calm :-)

I had my exchange about 6 weeks ago, and last week was also feeling that squishy sound. This week I have not felt/heard it.

I am also experiencing this noisy sound when I move my arms up. Do you ladies still have this problem? Frustrated. Hope I don't have to listen to this forever.