You can have shoulder dislocation or shoulder separation. They are two different things. You overuse your shoulder and put weight over time. You will tear soft tissues; tendon and ligament and this is called shoulder dislocation.
In my case, I had a bad ski fall and took a severe impact on the left shoulder. I use a shoulder brace and slept on the good side. I made sure I had full range of motion. Later you start getting back full motions, the more difficult it gets.
After this injury, whenever I load my shoulder or overuse, it tends to hurt. So, I do these exercises to keep pain away.
Modern medicine changes its procedure and have a patient sit up within 24 hours of an open heart surgery.
However, I learned hard way that your shoulder is complicated and requires active rehabilitation to recover. You need a rehab to stabilize.
See this simple video just using nothing but a rubber band. Here is another video with good explanation by Expert Village. Here is another video. The gentlest one is this video.
You should do these exercises to both sides.