It honestly sounds like a coincidence. Perhaps you are allergic to an ingredient in the hair dye. That's probably why your rash is located all near your head.
I hope you stop itching soon. Just a tip - preparation H worked well the last time i had hives, they stopped the itching and took the swelling down.
Welcome Home !! Great to hear your back safe and sound on "home" land!
Look forward to see how your doing.
Teresa
I replied to your post on the other forum ~
Best Wishes