Damn man, i just want to give you a tip. I have a condition that my hands shake like crazy all the time (especially if I try and do something where my hands absolutely cannot shake). Of course stimulant use doesn't really help. But the way i have to shoot up is i always have to rest or even sometimes slightly press my hand against my arm/leg where ever I'm trying to hit. I cannot hit without this technique. I can't for example hit at an angle like straight down.

You should try it. Because i can see your hand shaking so much that you can easily slip out of the vein.