Hair Dye advice

I have naturally black hair and am going grey at 22, I had been dying it black to cover the grey and 6 months ago I decided I wanted auburn hair. The hairdresser I went to bleached my hair twice! And then put the dye in my hair 2 or 3 times. My hair was so frizzy and unhealthy that I hated looking in the mirror. My hair really felt like straw. I cut my hair to about 2 inches long and it is now back to it`s natural color. The problem is I hate short hair. My hair had originally been past my shoulders. I need some serious advice on dying the grey hair without damage and also on products that help speed hair growth. Please help my hair is 2 inches eek! ! !