IS it true if I inject in my chest or in my shoulders my upper body will get a bigger work out or bigger because of where im injecting at??
NO. Whatever it is you are injecting has to be absorbed in your body first before it will start to work. That means it is in your blood - not just you upper body blood, but all of the blood in your body.
Don't worry about building just your upper body - you will look like a freak if you don't work your legs.