My body has always had very strange reactions to anxiety and my physical symptoms have changed over time.

In my early 20s, I developed performance anxiety, which mostly popped up in an office setting (especially in a conference room). Anytime the focus was on me and I got the slightest hint of nerves, I immediately changed 6 different shades of red, with noticeable blotches (hives?) forming under one of my eyes, on the side of my face, and on my neck. I've learned to cope with this, somewhat, over the years and it has slightly improved as I've build confidence in myself and my ability to perform at a high level in my role. 

A year or two back, I got faint hives during a public speaking event and I developed a VERY itchy rash on my left arm right next to my elbow. After that, the rash would reappear every time I had an incident. More recently, the rash has returned and persists, even when I'm not feeling anxious at all, except now it's not visible. It is still very itchy and I just find it very strange how my anxiety could manifest this type of reaction from my skin. 

Has anyone experienced anything similar to this? It's a minor inconvenience compared to what others suffer I'm sure, but I'm still curious.