Swelling after mastectomy

I had my right mastectomy with SNB and under pec muscle expander six days ago. Almost back to full range of motion and pain isn't too bad. I have one drain and I don't think it will be coming out in the next few days even though the numbers are going down.

I am able to go back to some light activities at home and go for short walks a couple of times a day. Doing my exercises religiously, I am following written PT recommendations.

Unfortunately, even lightest activity ends up in swelling in upper part of the breast going all the way to the armpit. I am trying to learn to pace my activity, take many breaks, put a pillow under my right arm, change position while I am sleeping to reduce the swelling, and rest.

Just wanted to hear others with similar experience.. for how long it could last? What are the other things to do to reduce this swelling? I thought being active (and taking breaks of course) was a good idea, so how do I know when it's too much?

Thank you everyone.

Thank you for your response FrenchPorsche,

Intuitively I feel that not moving at all prevents swelling, but for sure creates other issues. I am seeing my doctor next week, I am guessing they are going to repeat same old - listen to your body. Looks like I am not alone.. wishing you a speedy recovery.