ive done 3 cycles before this one, im currently on sust/primo cycle in my 1st week, but in my butt the scar tissue never healed, so the other day i took my needle and jamed it in my ass where i usualy do but it didnt go in. I had to lean the needle against the wall and shove it in, theres like a ball in my butt area and it hasnt went away. I can no longer shove pins into my butt area and I need a new place to shoot, Ive never put a pin execpt a slin pin in my shoulder and I was wondering what size pin can i use for my shoulder with sust and also if this scar tissue goes away or should i just continue to jam it in there real hard..?