I have just injected my self with meth into my vein and it has swollen up and hurts I have missed the vein or busted it wot can I do to reduce swellin?

Seek medical help. Injecting meth can cause local skin necrosis, cellulitis and deep tissue infections, not to mention endocarditis with destruction of your heart valves. Stop shooting up and seek medical attention asap. If a severe local infection developes you could potentially lose an arm. Best of luck to you.
Need. help with drug abuse counseling and treat possible skin infection. A listening PCP will be able to assist with treating the infection and referring you for drug abuse treatment.
See doctor. A reaction like you describe puts you at very high risk for soft tissue infection like cellulitis or phlebitis. You should see a doctor for an evaluation.