@4Coco ... is there swelling at the area that you are experiencing the 'tightness discomfort'? If you press the swelling .. does the fingermark remain? There is often discomfort for the first few months particularly or longer. :(
My surgeon organised my appt with a Lymphoedema specialist shortly after my surgery .... maybe if you ask your Onc to refer you to one, instead of the OT, it would more efficient for you - see the OT afterwards for exercise advice, if needed? She showed me the correct 'massage' method to & what to 'look for', should I need to see her again.
take care & all the best xx
