It’s called a Posterior Dislocation. 

Basically, the upper joint on my humerus was forced out of its socket in the shoulder towards the back rather than out the front like the majority of dislocations tend to occur. I can’t say from personal experience whether one is more painful than the other as this is the first time I’ve ever dislocated my shoulder. All I can say is that it hurt… A LOT.

The real question is with respect to the severity of the damage I’ve done. Have I torn my rotator cuff? Only an MRI will tell me and that’s something that I’m booked in for tomorrow evening. From there, I find out if I have to go under the knife to repair it. The suspense is killing me, I swear.