You hit it on the head to much fert.I would flush it with straight h2o let it run threw until you see clear water coming out.Sorry i dont no what your growing in soil or hydro.Any ways if its soil flush with gallon of water wait a couple days and only fert 1/4 of recommended dose wow i sound like a doctor.Anyways dont worry it will come back quick.Peace and keep on growing.P.S. easy with that miracle grow powerfull shit.