3 weeks post mastectomy - Just wanted to say hi!

Hi in February I wasI diagnosed with Invasive Ductual Carcinoma Gtade 3 - ER positive/PR negative and HER positive.  I had DCIS in 2023 and had a lumpectomy and radiotherapy, so I had to have a mastectomy.  I am 3 weeks post surgery and now just waiting on Oncology Team as so need to have Chemo.  I am struggling with my right side - I feel like I am wearing a plastic brace!!!  Any ideas for relieving the stiffness.  Take care Jx