I had anterior shoulder pain for quite some time. Each night before my upper body workout, I have my wife gua sha the hell out of me, specifically my front delta down to my pecs, top of my pecs, back of my shoulder where the shoulder meets the lat, and the lats themselves (oooouuuch!).
Ever since doing this, not only do I have no shoulder pain, but my shoulders are better aligned. My left shoulder used to bother me and it was pulled back further than the right one. Since doing gua sha regularly, they’re now almost even. I believe the issue was tightness in the back of my delts was pulling something back and creating pain.
The other posters’ give solid advice, too, take it! But my experience has always been stretching and getting blood flow into the areas you plan to lift with a day or two before. I hope that helps and your shoulder feels better soon!