I've Been Injecting Meth For A Few Months Now. On

I've been Injecting meth for a few months now. On and off. But the last few times it seems my body is rejecting it. My legs and arms beco.e hot and swell. Feeling tight. With not very good Capillary refill. But then the next day it's almost back to normal. What could be causing this? It's been a few weeks now. I would imagine if it was infection I would be very sick. Could it be my lymph nodes or arteries?