I started using a 5/8's pin for my shoulders, then I decided to change it up and use a 1" to make sure I got it deep enough. I noticed I started getting slight swelling in the inject site, that would go away after a few days, But I never had swelling with the 5/8's pins. Im using 1 cc of test 2x a week rotating shoulders. Think I'm ok going back to 5/8's?