Just to ease the pain, even when you dont feel anything after make sure to massage it for about 5 mins. That way it wont hurt the next day. Sust is pretty thick, 250mg per ml so running the amp or the syringe under warm water thins it up a bit. You can just run the amps in warm water before drawing.
!Make sure to massage because you wont feel anything after but without massaging you will the next day. on my first cycle, which I am guessing this is yours, I shot 3 cc's of sust in the glute when warmed and massaged and I had no pain the next day. Check out general injecting tips and it will be fine. Use the search button.