Alright as you all know Injuries happen, but there are lots of ways to prevent them and help them to heal.
When you do have an injury REST!!! your body needs rest, i am the worst one to teach this cause i hate not working out, but in order to get better let the muscles, bones, nerves, and ligaments heal. Even if you just get to the gym and you feel your shoulder hurting, stay away from it. Do lower body and switch it up and give it rest.
Stretch, Strecth, Strecth, that is the best way to prevent 95% of all gym injuries. The warm-ups that are provided are to do AFTER you stretch. Do full body stretches, legs, back, shoulers arms, calves, all of them. because when you do High Impact workouts your using other muscles that you think you have used, but prob haven't.