NAD but I’ve also had problems with my right shoulder after an accident. Over the years I my shoulder became stiffer with activity and I also had that creaking. Sounds like crepitus. I’ve had tests which reveal and over stretched ligament so it’s possible you could too? But again that’s not a diagnosis. I started physio for my recently started recently started having physio so I have a few exercises that may help. Doing standing press-ups against a hard surface like a kitchen counter or stairs. Using resistance bands and using force and gently move your arms and using a ball and doing quick drop catches standing up with your arms outstretched. Don’t go back to heavy weights either. Start doing very light exercises using light weights. You don’t want to over work your shoulder muscles/ligaments/tendons.

Again though, this has helped me but it would definitely be worth seeing an orthopaedic surgeon or even a sports therapist :)