Injured shoulder working, advice on healing/future injury prevention?

I’ve been grooming for about 5 months, and in the last couple days messed up my right shoulder. My dad is pretty knowledgeable in injuries of all sorts, and based on his evaluation and some googling I think I did something to my rotator cuff. My shoulder blade area is painful and feels inflamed, and the pain goes down through my upper arm. Using my clipper and brushing have been especially painful. I have been having it massaged, icing, taking Advil, and doing targeted stretches everyday to try to combat it. I’m trying to take it easy at work, doing mainly smaller dogs and take breaks. I would love any tips for quick healing, it’s no fun being hurt in the busy holiday season! And I would hate to have it turn into a chronic issue. Any advice on mending the current injury, and more long term injury prevention for once I’m in better shape would be appreciated!