Huh depending on medium it prob is to hot i would suggest goin out and buying new soil without any nutes in it re transplant taking extra care not to disturb root ball to much
my guess is every time you water your releasing more and more nutrients so flushing isnt helping at all
monitor your ph you want min 6.4 to 7.0
And as for feeding young plants its what you should do paying extra care not to go over board i my self feed 450 ppm to a 3 - 4 " clone and by 14th day in the 750 to 800 plants love it 14 days and there 14 - 18 " tall
PS: i would suggest investing in superthrive to help combat the high stress plants are takin right now once transplanted
good luck