Hi. I think you has dislocated your shoulder and again it has come back to its place. Please get yourself checked by a sports medicine specialist. In first time dislocation you need to immobilise the shoulder for 3 weeks and you may have good chances of healing. If this was a repeated dislocation then you need to get your xray and mri done to find out how much tear has happened in your soft tissues. Shoulder surgery in expert and trained hands gives wonderful results. So don't worry. But please do not ignore and delay.