Twisting leaves is from out of whack ph, if your ph drifts too far out either way up or down it will cause the leaves to twist, fix your ph and it will return to normal......dont fix it and they will all die within a couple days! i just went through it. an over nute looks like a bad overwater all the leaves droop down the only difference is the leaves get burned, depending on the strength of solution or organics.
labrat's suggestion is what needs to be done. a good flush then i would start with 1/4 strength ph'd solution then work back up. I just got back to full strength on my nutes 2 days ago. i went from 1/8 strength back up to full strength, and they are doing fantastic. how old are your plants? whats the media?
Cannabillion7......horticulture student? we should be asking you these questions......