three days ago i injected methamphetamine into my right arm , and everything was fine. I do not have track marks, nor have i used drugs intraveinously in the past. I understand that a bruise may appear if the needle was dull. I did not miss the shot, and now (3 days later) i have a pinkish brown bruise running along each side of the vein. Is this a blood infection? ... I know what a simple miss looks like, but this wasnt a miss. The needle wasnt brand new- it was used between a hep c/hiv/ aids free friend and myself, but cleaned thoroughly in between. before this arm, i had used it a few times on the other side. What could this be? Theres no swelling , no pain worse than a regular bruise, and it doesnt feel hot to the touch.