I'm currently going through the same thing right now. Pinned on Sunday and the pain was excruciating for days and then pinned my delt on tue and I'm still in pain. I personally think I mightve gone to deep when injecting because I did not have any pain from my previous shots, except the first couple. This is prop by the way I honestly thought I had an infection because the pain was similar to when I got an infection years ago but it was not hot to the touch or red so I just applied pleny of heat to it andit seemed to do the trick. The pain in my delt is still there and is lasting longer than the reaction from the pain in my glute. I'm just going to give it a few more days. I pinned twice after that so I know its not the gear.