I have a rash on one of my arms and I've had it for 2 days. Its a bunch of small red bumps and it feels like its on fire when I itch it.
Red vesicular rash. 18 year old with painful burning vesicles on arm. Get a full medical history and in person physical exam ASAP. You can try a consult in your area as well. If the rash is itchy (pruritic) and painful you need to give more history. The differential is large and it could be anything from zoster to contact dermatitis to chiggers or a reaction to insect bites, bedbugs, or scabies. A picture=1k words.