I've had my hair streaked before - only last year. I'm having some more highlights put in tomorrow afternoon and only just remembered at 3pm today about the arm patch test thingey. I didn't have a reaction to it last time.
Shall I be honest with the hairdresser? I know she won't do it if I admit it's only been on for 24 hours, not 48! Will she be able to tell by looking at the little black hexagons?