I have natural mid/light brown hair going grey and tried a brown permanent shade on my hair but looks terrible. Left for a few months and now have horrible greys and regrowth issues - hair disaster indeed. So I want to change tack althogether and go dark blonde, is this possible at home? Can not get an app at my hairdresser and the colourest did say he wouldn't change my colour to blonde - not too sure why but did have my hair that colour for over 20 years and change to brunette in the last 5 years. Any advice before I hit Boots?