Hiya hope this helps...My mum has a condition called vitaligo. This is where you start to losr the pigment in your skin (hence the white patch), this can also affect hair colour (thats y some people have very white hair). My mum went through pretty much the same thing and it was hard for her at first, I mean if you lose hair colour normali u can dye it but she was allergic. All I can say is keep and eye on it and if u find nemore just go and see a doc so u can be reassured it is vitaligo.
Hope I helped! X