I have yellow hair! help

ok so I dyed my hair brown, but I hated it. So a few hours ago I bought light blonde to try to get my blonde hair back, only instead it turned this really light yellow colour! It's really really light, and it doesn't look horribly bad because my skin is light too, but in the sunlight it doesn't look right. It's too much of a warm colour, and I think I have to turn it into a cool colour. What can I do to just cool down the yellow? it'll look fine if it's just a more natural colour, if I got a light ash blonde hair dye would it make my hair darker? my hair is soo damaged right now, I'm afraid it'll fall out if I do anything else to it

Edited by yumyumkiwis