Yuppers... it's deft burnt. If you flushed it that's pretty much all you can do. The new growth looks good,just a little bit of clawing. You have to just wait it out, I think it will be ok now.
The new growth looks like it's reaching to the light, so that's good. I personally never go by the directions on the nutrient bottle. I will do quarter strength to half strength during veg then pump it up a little during flower. I would wait another week depending on how the new growth keep going. And when you do start nutes I would start 1/4 strength. Do you have ppm meter/ ph pen?