My Friend Started Shooting Meth. She Missed A Little And

My friend started shooting meth. She missed a little and has a bruise. She did some again and couldn't hit the vein. She didn't miss this time, but one of the times she poked herself ,and tried to register, she pulled th needle out to try another spot. Well now there is a small bump that hurts where she didn't even inject anything. This was just over an hour ago. What can I do to treat this? And how can I help the bruise from the missed shot go away.
She promised me to stop the needle if I help. She only started a few days ago.