Well, I just talked to my buddy about this problem, and, he basically broke it down like this...
"The pain you are getting is from the alcohol and benzyl benzoate in the preparation you injected. to dissolve such a high concentration of test, they have to use high amounts of these solvents. Your product must not have an ethyl oleate carrier, which is a chemical designed to stop the pain from occurring from injections. i suggest using a product that contains ethyl oleate next time. you're best bet is to just inject less and stick to injecting in the glutes and quadriceps. dont inject that in your shoulders. Over time you will get used to this and the pain will start to go away, but it may take a while for your body to get used to all the benzyl alcohol."
I already posted this in another thread, but, I thought I would create a thread for this issue all by itself, for those interested.