Undiagnosed itching

About 5 months ago, I've been getting a reoccurring itch almost everyday when I do something strenuous such as dancing, working out, or sometimes just when I'm walking. I say itchy because I'm not sure what else to call the sensation, it's more of a prickly feeling, and its very irritating. It usually lasts anywhere between 2-5 minutes, and it covers my body neck down and above my feet. When I scratch theres little relief and to avoid looking like I'm insane in public I usually have to stop whatever I'm doing and not move until the feeling is gone. When I'm home, I've taken off all my clothing when I get the itch, and I notice no bumps, coloring, or anything on my skin. So I've somewhat learned to live with it for the past 5 months, because I can't find out what this is. I've tried using different soaps, detergents for clothing, not using cloth softener tissues, but none of my efforts have brought relief. I don't know how it all began. Any idea what it might be? I appreciate the help.