I dyed my gray hair...

I had no choice but to get my gray hair dyed for a family event before I had fully recovered from a bad cold and body aches. Even though I went to the same salon and had the same stylist do it, my hair was particularly damaged this time, and I even got dandruff. My scalp hurts, so I can't even shampoo properly, which makes me sad.

What are some particularly good methods for this situation, and are there any specific products available? Please recommend the shampoo, conditioner, or nourishing products you are currently using.