Anxiety Support Group
Anxiety is a physical condition marked by intense and persistent feelings of distress, fear, angst or dread. General anxiety caused by routine day-to-day stresses usually passes quickly and is experienced by almost everyone at one time or another. However, such feelings that linger over time and are very difficult to cope with, and which lack a clear cause, may indicate...

Could be something you ate (allergic reaction), or maybe a bug bite or if you were outside and touched grass or plants, etc.
Maybe eczema, dry skin, etc. Lots of things it could be. Even because of your laundry detergent, a new body soap, etc.
It will probably go away in a day or two.
They do go away. To keep from making it worse, use a cream to help distract the irritation.
Focus on some specific task to distract the brain.