It looks like a staph infection to me. I am surprised they didn't make sure you started on an antibiotic and sent you home from work.
When i went into the E.R. Last monday , they gave me a corto steriod shot, and yes they did give me antibiotics, and cortizone cream and predizone, they also did 2 swab cultures but come to find out the NP didnt send them into the lab, they dont know where they went, they sent me back to er, for second round of cortizone shot and antibiotics, and some itchy pills, when i found out they never had my cultures and never sent them in to be tested, I was fuming, bc i am busy working and i have no clue what this crap is, it is still on my arm but the swelling went down the itching is very min. its still blotchy looking with scaling and peeling , when i went in yesterday to one of the ladys who does shots and releases u back to work , she said it looked like shingles, also the pharm. said same thing, anyways i still have it but its getting much better, i did also have it on my face, still 2 small blotches but very light, also noticed too my cheeks have been getting really red like i have a fever and a small red line down my nose. it happen 2x so far. yesterday and the other day, could it be from the predizone ?