I had this same reaction. I was eating large amounts of oranges, juicing mostly, and my skin freaked out, totally. But I was way past the detox phase, so I knew it wasnt that, and they were organic as well. I took them out of my diet, and recently tried again, and the same thing happened. I get flushed and hot as well. I have read recently that oranges can cause a rosacea flare up, so maybe you have rosacea, and its never been a problem for you until you introduced large amounts of a flare up causing food, like oranges.
How is your skin now after a few weeks?