What Causes Swollen Fingers After Injecting Heroin In Left Hand?

I believe I shot heroin into an artery on my left hand, I m actually certain that I did, it felt like hot water spread under my skin and the liquid spread under my skin very fast, I pulled the needle out quickly,my pointer,middle, thumb and ring finger began to swell and I had a panic attack.I was so tired I just iced it and put it in cold water and now about 12 hours later after sleep, the swelling has gone down a bit but it s still swollen and sort of tingling,I seem to have circulation in my hand. Checked by pressing my nails for a couple seconds to turn them white and watch them turn back to color.Should I go get medical help?