TweetWell it depends on what brand prop you are using. Prop in my thigh always hurt. But not my arms, I could go pump iron after inj in my delts. Are you being careful with the needle not to spin it, not to squeeze it to hard? Also rubbing the area afterwards helps out alot. Also you can apply heat to it. It makes it better right away, but once you remove the heat it starts hurting again. I have had it to make my azz so sore I had to lean to one side while I was driving. Everyone looking at you funny!!!