Hello, I hope that I can address your question. Given that you are injecting a toxic substance, it sounds as though you may be having a reaction to the meth you injected. This may be something benign like a scar at the injection site/local tissue damage to something very serious like a venous clot. In addition injecting street drugs can cause serious bacterial infections, not to mention the possibility of catching blood borne diseases and osteomyelitis. You would be best served by being evaluated by a physician with an ultrasound of your arm (in the least), as well as being treated for drug addiction. I hope this helps.